Ever craved a bowl of tomato soup that feels like a warm hug, but you also wanted to do literally nothing for hours? Same here. I threw this slow cooker tomato basil soup together on a busy Sunday and it saved dinner—and my sanity. If you like simple, cozy, and slightly fancy moods without the fuss, you’ll love this.
I’ll walk you through everything: why this recipe works, what you need, how to make it step-by-step, clever tweaks, and what to do with the leftovers when you inevitably make too much. Curious how a few pantry staples turn into something silky and lush? Stick around. Also, if you love roasting flavors, you might enjoy this roasted tomato basil soup I tested last month—different vibe, same tomato obsession.
Why You’ll Love This Recipe
- Hands-off cooking: Toss, set, and forget for 6–8 hours. Yes, you really can leave the house.
- Big flavor from few ingredients: Canned tomatoes, basil, and garlic pack serious punch without drama.
- Creamy without a blender if you don’t like fuss: Stir in cream or coconut milk at the end for silky texture.
- Kid-friendly and adult-approved: Add a splash of hot sauce for grown-up heat or make it mild for picky eaters.
- Perfect with homemade croutons: Those Parmesan cheddar croutons lift the whole thing into soup-celebration territory.
Ingredients You’ll Need
- 2 cans (14.5 oz each) diced tomatoes
- 1 cup vegetable broth
- 1 medium onion, chopped
- 3 cloves garlic, minced
- 2 teaspoons dried basil
- 1 teaspoon salt
- 1/2 teaspoon black pepper
- 1 cup heavy cream or coconut milk
- Parmesan cheese for croutons
- Bread for croutons
See? No weird items that require a farm visit. Keep the ingredients bolded items in mind when you shop.
How to Make (Step-by-Step)
STEP 1
In a slow cooker, combine diced tomatoes, vegetable broth, chopped onion, minced garlic, dried basil, salt, and black pepper. I always give the tomatoes a little crush with the spoon to wake them up.
STEP 2
Stir to mix well, cover, and cook on low for 6–8 hours. I usually set it before I head to work. The house smells amazing when I get back—no humble brag, just truth.
STEP 3
About 30 minutes before serving, stir in the heavy cream or coconut milk. I add it late to keep the color bright and the texture velvety.
STEP 4
For the Parmesan cheddar croutons, preheat oven to 375°F (190°C). These croutons turn plain soup into party soup, FYI.
STEP 5
Cut bread into cubes, toss with olive oil, grated Parmesan cheese, and any additional seasonings (garlic powder, a pinch of paprika). I throw in a little black pepper because I like life with contrast.
STEP 6
Spread on a baking sheet and bake for 10–15 minutes or until golden brown. Watch them after 10 minutes—one second they’re perfect, one minute later they could audition for charcoal.
STEP 7
Serve the tomato soup hot, topped with the croutons. Add a little fresh basil or a drizzle of olive oil if you want to look chef-y.
Ingredient and Method
This section pulls the practical pieces together: the Ingredients list above tells you what to buy and prep. The Method consists of the slow-cooker steps (STEP 1–7). Follow them in order and check textures at the 6-hour mark. I recommend tasting and adjusting salt at the end—tomatoes vary, and your taste buds deserve respect.
Pro Tips for the Best Results
- Use good canned tomatoes: I always choose a high-quality brand—flavor matters here.
- Sauté the onion first if you have time: I skip this on lazy days, but it adds depth.
- Don’t boil after adding cream: Heat gently so the dairy doesn’t separate.
- Adjust acidity with a pinch of sugar if needed: Tomatoes can get tangy; a little sugar balances the flavors.
- Blend for extra silkiness: Use an immersion blender for smooth texture; I do this when I want to impress someone.
- Make croutons in bulk: They store well for a week and upgrade everything from salads to soups.
- Taste before serving: Salt and pepper change the whole mood—don’t skip.
Fun Variations & Topping Ideas
Variations:
- Vegan version: Swap heavy cream for coconut milk for creaminess without dairy.
- Smoky twist: Add a teaspoon of smoked paprika or stir in a few roasted red peppers.
- Meaty upgrade: Brown a pound of Italian sausage and add before serving for a heartier bowl.
- Herb swap: Use fresh basil at the end for a zesty green pop—add 1/2 cup chopped fresh basil.
Toppings:
- Parmesan cheddar croutons (obviously)
- Fresh basil leaves or a basil chiffonade
- A drizzle of olive oil or basil pesto
- Cracked black pepper and red pepper flakes for heat
- A swirl of cream or coconut milk to make things look professional (and taste luxurious)
Storing and Reheating
- Refrigerate in an airtight container within 2 hours of cooking. I usually divide into single-serving containers for quick lunches.
- Keep refrigerated for 3–4 days. If I won’t finish it, I freeze portions for up to 3 months.
- Reheat gently on the stove over low-medium heat. Stir frequently and add a splash of broth if the soup thickened too much. I avoid microwave reheating for the first minute, then heat in 30-second bursts to keep texture even.
- If frozen, thaw in the fridge overnight before reheating, or use the defrost setting on your microwave.
Leftover ideas
- Tomato soup pasta sauce: Toss with cooked pasta and a handful of Parmesan. Delicious and lazy.
- Shakshuka-style eggs: Simmer the soup, make little wells, crack eggs, and bake until set. Fancy-looking brunch, zero fuss.
- Creamy tomato risotto base: Use the soup as broth and flavor base for quick risotto. Instant upgrade.
- Sandwich dip: Serve with grilled cheese for dunkable, nostalgic perfection. IMO the only way to eat a grilled cheese. 🙂
Frequently Asked Questions (FAQ)
Can I use fresh tomatoes instead of canned?
Yes. I sometimes roast fresh tomatoes and peel them before adding. Use about 2 pounds fresh tomatoes, and add a little extra broth because fresh ones contain more water. Roasting improves flavor if you have time.
Can I make this in an instant pot instead?
Yes. Sauté the onions in the Instant Pot, add the tomatoes and broth, then cook on manual high for 10 minutes with natural release. Stir in cream afterward. I use the slow cooker when I have time, but the Instant Pot saves the day on busy nights.
Is coconut milk a good substitute for the dairy?
Absolutely. Use full-fat coconut milk for the creamiest texture. The coconut flavor stays subtle under the tomatoes, but if you worry about flavor crossover, use heavy cream instead.
How do I make it less acidic?
Add a pinch of sugar or a teaspoon of baking soda while stirring; both balance acidity. Taste as you go—you want balance, not dessert soup.
Can I double the recipe?
Yes, double everything except the cream until the end. Slow cookers vary, so ensure you have space; I avoid filling mine more than two-thirds full.
Conclusion
This slow cooker tomato basil soup checks all the boxes: easy prep, rich flavor, and comfort in a bowl. It fits weeknight chaos and slow Sunday vibes equally well. Try the base recipe, then experiment with toppings or swaps—your future self will thank you. If you enjoy variations and want another slow-cooker comfort option, check out this great recipe for inspiration: Slow Cooker Creamy Tomato Basil Soup – The Chunky Chef.
Leave a comment and a rating if you try this—I read every one and I actually care what you think. Also, tell me your favorite crouton mix; I judge people kindly based on their crouton choices. 😉
Slow Cooker Tomato Basil Soup
Ingredients
Method
- In a slow cooker, combine diced tomatoes, vegetable broth, chopped onion, minced garlic, dried basil, salt, and black pepper. Crush tomatoes slightly with a spoon.
- Cover and cook on low for 6–8 hours.
- About 30 minutes before serving, stir in the heavy cream or coconut milk.
- Preheat oven to 375°F (190°C).
- Cut bread into cubes and toss with olive oil, grated Parmesan cheese, and any additional seasonings.
- Spread on a baking sheet and bake for 10–15 minutes or until golden brown, watching closely to prevent burning.
- Serve the tomato soup hot, topped with croutons. Add fresh basil or olive oil if desired.
