Deliciously Simple Vegan Lentil Soup Recipe

Have you ever craved a warm, comforting bowl of spaghetti but dread the thought of spending all day slaving over the stove? Fear not, my friends! I have the perfect solution for you: crock pot spaghetti sauce. This vegetarian recipe is not only easy to make, but it’s also packed with all the hearty and delicious flavors you’re looking for in a classic spaghetti dish.

As a vegan chef, I believe that everyone deserves to enjoy a steaming hot plate of spaghetti – without sacrificing their dietary restrictions. That’s why I’ve created this veggie-loaded crockpot spaghetti sauce that’s perfect for vegetarians and vegans alike. But don’t let the lack of meat fool you; this recipe is just as savory and satisfying as any classic meat-based sauce.

With simple ingredients like diced tomatoes, onion, bell peppers, and carrots, this recipe is easy on your wallet too. And what’s more, it can easily be adapted to include additional veggies or proteins like mushrooms or plant-based meats.

So go ahead and give this slow cooker spaghetti sauce recipe a try! It will quickly become one of your go-to recipes for a quick, delicious weeknight dinner that won’t leave you feeling guilty or bloated. Trust me, once you taste it, you won’t be able to resist coming back for seconds.

Why You’ll Love This Recipe

Vegetarian Crock Pot Spaghetti Sauce
Vegetarian Crock Pot Spaghetti Sauce

Listen up, foodies! I am here to tell you about the most mouth-watering vegetarian crock pot spaghetti sauce recipe that you will ever lay your taste buds on. You may be wondering why you should try out this recipe when there are numerous spaghetti sauce recipes out there. Well, let me ask you this – have you ever tried a veggie-loaded spaghetti sauce? Trust me, it’s an absolute game-changer.

This slow-cooker spaghetti sauce is so chock-full of delicious veggies like green bell peppers, carrots and onions that it’s almost bursting at the seams. For all my vegetarian comrades out there, this meatless spaghetti sauce recipe is the best way to get your daily serving of vegetables in without even realizing it. The marinara sauce has a perfect balance of sweetness and tanginess because of the addition of sugar, tomato paste, diced tomatoes with seasonings and tomato sauce.

Now, don’t get me wrong, I love me some parmesan cheese sprinkled on my spaghetti as much as the next person. But sometimes I must admit, I crave something more. Enter this vegetarian crockpot spaghetti sauce that is so hearty and scrumptious that it doesn’t even need any cheese to seal the deal. Whether you’re feeding a crowd or looking for leftovers for days, this veggie-packed spaghetti sauce is sure to be a hit.

So what are you waiting for? Get those slow cookers out and whip up this incredible homemade spaghetti sauce for dinner tonight. Your taste buds (and waistline!) will thank you for it.

Ingredient List

 Perfectly cooked pasta, smothered in a warm, hearty sauce, ready to comfort you at the end of a long day.
Perfectly cooked pasta, smothered in a warm, hearty sauce, ready to comfort you at the end of a long day.

Here comes the fun part – the ingredients! This crockpot spaghetti sauce is loaded with fresh vegetables and pantry staples, all of which come together for a veggie-loaded sauce that is full of flavor. Here’s what you’ll need to add to your grocery list:


  • 1 medium yellow onion, diced
  • 2 carrots, peeled and chopped
  • 1 green bell pepper, diced
  • 1 red bell pepper, diced
  • 2 garlic cloves, minced (or use 1 tsp garlic powder)

Canned Goods

  • 1 (28 oz) can crushed tomatoes
  • 2 (14.5 oz) cans diced tomatoes with seasonings
  • 1 (6 oz) can tomato paste
  • 1 (8 oz) can tomato sauce

Spices & Seasonings

  • 2 tbsp olive oil
  • 1 tsp salt
  • 1 tsp sugar
  • ½ tsp black pepper
  • 1 tsp dried oregano
  • 1 tsp dried thyme
  • ¼ -½ tsp red pepper flakes (depending on how spicy you want it)

Pro tip: For the freshest taste, you can also use fresh tomatoes instead of canned. Simply blanch the tomatoes to peel them and chop them roughly to replace the canned diced tomatoes. Plan on using about two cups of chopped fresh tomatoes in place of each can of diced tomatoes.

The Recipe How-To

 This sauce is full of robust flavors and chunky vegetables that will add a surprising twist to traditional spaghetti dishes.
This sauce is full of robust flavors and chunky vegetables that will add a surprising twist to traditional spaghetti dishes.

Step 1: Prep Work

To start off, gather all the ingredients you will need for this vegetarian crockpot spaghetti sauce recipe: diced tomatoes with seasonings, tomato paste, crushed tomatoes, tomato sauce, onion diced, green bell peppers cut into one-inch pieces, carrots peeled and chopped, minced garlic, olive oil, oregano, thyme, red pepper flakes, salt, and sugar.

Step 2: Sauté The Vegetables

In a skillet over medium-high heat, heat 2 tablespoons of olive oil. Add in the diced onion and let it cook while stirring occasionally until it softens. Then add the green bell pepper and carrots to the skillet and stir occasionally until they become tender. Once done transfer them into the slow cooker.

Step 3: Slow Cooker Work

Pour into the slow cooker two 28-ounce cans of diced tomatoes with juice. Next stir in one 6-ounce can of tomato paste and one 15-ounce can of tomato sauce. Add in one tablespoon of dried oregano and one tablespoon of dried thyme. Then add a pinch of salt and sugar to taste. Mix all the ingredients together really well.

Step 4: Cook Time

Cover your slow cooker and let it cook on high heat for about four hours or on low heat for eight hours so flavors are released allowing all-natural juicy goodness steep into the vegetables creating the deliciousness.

Step 5: Perfect Results

Afterward uncover the lid and give a quick stir for those final touches to check desired consistency then adjust accordingly. Once complete you have an aroma that tantalizes taste buds bringing hearty savory joyfulness to all.

Enjoy your homemade spaghetti with this veggie-loaded spaghetti meat sauce, you won’t even notice there is no ground beef or Italian sausage present in this dish.

Substitutions and Variations

 Get ready to enjoy a no-fuss meal that cooks itself while you go about your day with our crockpot spaghetti sauce!
Get ready to enjoy a no-fuss meal that cooks itself while you go about your day with our crockpot spaghetti sauce!

Are you feeling adventurous and looking for ways to spice up your crockpot spaghetti sauce? Here are some substitutions and variations to try:

– Veggie loaded: If you want to pack in more veggies, try adding mushrooms or zucchini to the mix. You can also replace the green bell pepper with red or yellow ones for a sweeter flavor.

– Homemade spaghetti meat sauce: If you’re missing the texture of meat, try adding ground beef or Italian sausage to your spaghetti sauce. Just brown them in a pan with olive oil and add them to the crockpot along with the other ingredients.

– Marinara sauce: If you don’t have tomato paste, diced tomatoes or tomato sauce on hand, try substituting them with marinara sauce instead. You can adjust the amount of sugar you use accordingly since marinara sauce is already seasoned.

– Fresh tomatoes: Instead of canned tomatoes, you can use fresh tomatoes for a brighter flavor. Cut 1 inch pieces of green bell pepper and sauté it with chopped onions and garlic in 2 tablespoons of olive oil until it becomes tender. Add fresh tomatoes, salt, sugar, and black pepper. Cook for 3-4 minutes until everything is combined.

– Spaghetti recipe swapping: Wanting more variety? Use different shapes of pasta like fettuccine, rigatoni or penne instead of spaghetti. You can also try using gluten-free pasta if you have dietary restrictions.

Keep in mind that when substituting ingredients or varying the recipe, it may affect the overall taste and consistency of your dish. Don’t be afraid to experiment but start small and see where it takes you!

Serving and Pairing

 A hearty herb-infused tomato sauce that will make your tastebuds dance with joy!
A hearty herb-infused tomato sauce that will make your tastebuds dance with joy!

Now that you have crockpot spaghetti sauce simmering away, it’s time to start thinking about serving and pairing options. One of the best things about this vegetarian crockpot spaghetti sauce recipe is that it perfectly complements a range of pasta varieties, from gluten-free noodles to traditional spaghetti.

I recommend serving the sauce piping hot over your favorite pasta noodle. And, for a true taste explosion, garnish with freshly grated Parmesan cheese.

But why stop at pasta when you can also pair this veggie-loaded sauce recipe with other dishes? This slow cooker spaghetti sauce makes for an excellent dipping sauce for bread, too. Just take a loaf of crusty bread and dip it right into the pot.

If you want to serve this meatless spaghetti sauce as the main dish, consider pairing it with a leafy green salad tossed with cherry tomatoes and balsamic vinaigrette dressing. Alternatively, roasted or steamed vegetables make a great side dish option.

But if you’re feeling adventurous, try using this crockpot spaghetti sauce as one component of homemade pizza. Spread the vegetarian crockpot spaghetti sauce over a pizza crust and add your favorite toppings such as mushrooms, olives, shredded cheese and bell peppers.

No matter how you choose to serve this best vegetarian crockpot spaghetti recipe, it’s guaranteed to satisfy every taste bud at the dinner table!

Make-Ahead, Storing and Reheating

 Top your spaghetti with a generous helping of this meatless sauce for an explosion of flavors.
Top your spaghetti with a generous helping of this meatless sauce for an explosion of flavors.

Now, let’s talk about making ahead, storing and reheating this veggie loaded crockpot spaghetti sauce recipe. This recipe is perfect for meal prepping and saving your time on busy weekdays.

I usually like to make a big batch of this slow cooker spaghetti sauce over the weekend and store it in an airtight container in my fridge for up to 5 days. If you want to store it even longer, simply transfer the sauce into a freezer-safe container and freeze for up to 3 months.

When you’re ready to enjoy this delicious vegetarian crock pot spaghetti sauce again, reheating it is a breeze. You just need to thaw the frozen sauce by transferring it from the freezer to your fridge overnight. Then, you can reheat on the stove-top over medium heat until warmed through.

One thing to keep in mind when reheating is that the consistency of the sauce may change slightly after being frozen. To fix this issue, add a little bit of water or extra tomato sauce before reheating it.

If you want to enjoy leftovers for lunch during the week, simply store them in glass containers with air-tight lids. When you’re about to reheat them in a work microwave, I suggest adding a small amount of water to help prevent the sauce from becoming dry and thick.

Overall, this veggie-loaded crockpot spaghetti sauce recipe is a great make-ahead and storing dish. It will save you time and effort while allowing you to enjoy delicious homemade spaghetti anytime you want!

Tips for Perfect Results

 Our mouth-watering spaghetti sauce is made with the
Our mouth-watering spaghetti sauce is made with the

It’s easy to make delicious vegetarian crock pot spaghetti sauce, but there are a few tips that can take your dish from good to great. Here are my top tricks:

Firstly, always stir the sauce occasionally while it’s cooking to prevent it from sticking to the sides or bottom of the pot. Since slow cookers vary, you’ll want to keep an eye on how fast your particular model cooks and adjust accordingly.

Secondly, try cooking the onions and peppers before adding them to the slow cooker. This will help release their natural sweetness and enhance their flavor. To do this, simply sauté them in some olive oil for a few minutes until they are just softened, then add them to the crock pot with the rest of the ingredients.

Thirdly, if you prefer a thicker sauce, add more tomato paste or diced tomatoes with seasonings. If you like it thinner, add more vegetable broth or water.

Fourthly, taste and season as you go! Don’t be shy about adding more salt, sugar or spices as needed. When using canned tomatoes, I always recommend waiting until later in the cooking process to adjust seasoning since some canned tomatoes can be quite salty.

Lastly, don’t be afraid to experiment with different ingredients and flavor combinations. You could try adding meat alternatives such as ground beef or Italian sausage for extra heartiness or more fresh vegetables like zucchini or mushrooms for a veggie-loaded twist. You could also try making homemade spaghetti instead of using boxed spaghetti if you like your dish more elevated.

Follow these tips for perfect results and enjoy your delicious vegetarian crockpot spaghetti sauce!

Bottom Line


If you’re looking for a delicious and nutritious vegetarian meal that will satisfy your cravings, this Vegetarian Crock Pot Spaghetti Sauce Recipe is the perfect choice. This recipe is a powerhouse of vegetables and herbs that’s bursting with flavor and nutrition.

Whether you’re a vegan or not, this recipe is sure to tantalize your taste buds and leave you feeling satisfied. The combination of diced tomatoes, tomato paste, yellow onion, green bell pepper, carrots, and olive oil all merge together to create the perfect slow cooker spaghetti sauce. Adding your own twists with any optional meat substitutes like ground beef or Italian sausage can elevate the sauce to another level!

This recipe is conveniently prepared in a crockpot, allowing for minimal effort but maximum flavor. Once prepared, it pairs great with classic spaghetti noodles or any pasta of your liking.

So why not try this recipe now and experience one of the best vegetarian crock pot spaghetti sauce recipes out there? Giving yourself a veggie loaded meal has never tasted so good!

Vegetarian Crock Pot Spaghetti Sauce

Vegetarian Crock Pot Spaghetti Sauce Recipe

From Linda Larsen, Your Guide to Busy Cooks at
No ratings yet
Prep Time 15 mins
Cook Time 9 hrs
Course Main Course
Cuisine Italian
Calories 322.2 kcal


  • 2 tablespoons olive oil
  • 1 onion, chopped
  • 2 carrots, peeled and chopped
  • 2 cups sliced mushrooms
  • 1 green bell pepper, chopped
  • 2 (14 ounce) cans diced tomatoes with seasonings, undrained
  • 15 ounces tomato sauce
  • 6 ounces tomato paste
  • 2 teaspoons sugar
  • 1/2 teaspoon salt
  • 1/4 teaspoon pepper
  • 12 ounces spaghetti
  • parmesan cheese (optional)


  • Cook onions and carrots in oil in large nonstick skillet over medium heat.
  • Stir and cook for 4-5 minutes until tender. Add mushrooms and bell pepper and stir. Place vegetables into bottom of 4-5 quart crock pot and add remaining ingredients except spaghetti pasta and cheese.
  • Cover crock pot and cook on low for 7-8 hours.
  • Uncover, stir thoroughly, then leave cover off crock pot and turn heat to high.
  • Cook, uncovered, for 1 more hour to thicken sauce.
  • At this point the sauce can be frozen. Divide into smaller portions and cool in refrigerator.
  • Wrap, label, and freeze the sauce up to 3 months.
  • To thaw and reheat, thaw sauce overnight in refrigerator.
  • Pour into skillet and heat over medium heat, stirring frequently, about 15-20 minutes or until sauce bubbles and is thoroughly heated.
  • You can even cook the pasta until almost tender and combine it with the cooled sauce. Freeze as directed, and thaw as directed. You may need to add 1/4-1/3 cup water when reheating if freezing the pasta in the sauce.
  • Or you can go ahead and serve sauce with cooked spaghetti and grated Parmesan cheese. 6 servings.

Add Your Own Notes


Serving: 246gCalories: 322.2kcalCarbohydrates: 58.6gProtein: 10.9gFat: 5.8gSaturated Fat: 0.9gSodium: 813.9mgFiber: 5.5gSugar: 12.1g
Keyword European, Kid-Friendly, Onions, Spaghetti, Vegan, Vegetable
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