Easy Keto Tomato Soup Recipe

This creamy keto tomato soup is made with fresh, juicy tomatoes, roasted garlic, and onion, and is ready in under an hour!

Low carb tomato soup in a white bowl with tomatoes in the background.

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One of my favorite soups is this creamy tomato basil soup. I discovered that roasting tomatoes brings out their flavor. Serve this soup with Keto pretzel bites or 90 second keto bread for an easy low-carb meal!

Looking for more tomato recipes? Check out my Panera tomato basil cucumber salad, homemade chunky salsa with fresh tomatoes, and my lasagna with ricotta cheese. And if you want to do some canning, make my homemade salsa for canning recipe!

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Why You'll Love It
Ingredient Notes + Substitutions
How to Make Keto Tomato Soup
Jeri's Top Tips
Recipe FAQs
More Delicious Homemade Soup Recipes
Printable Recipe
Comments

Why You'll Love It

Best flavor: So much more flavorful than canned tomato soups.

Low-Carb and Keto-friendly: This soup is low in carbs, so you can still have comfort food without the carbs.

Customizable: Want to add some spice? Throw in some diced jalapeños or sprinkle in some red pepper flakes. Want extra protein? Toss in some cooked chicken, shrimp, or black beans.

Ingredients for keto tomato soup measured out and placed on a wooden table.

Ingredient Notes + Substitutions

Tomatoes. I used fresh-picked tomatoes, but any kind will work. Beefsteak and Roma tomatoes work well, as do cherry tomatoes. Yellow tomatoes are also delicious and lower in acid.
Onion. I used an entire red onion, but you can use a yellow onion or a white onion.
Garlic. I used a whole garlic bulb. You don't even have to peel it! Just cut off the top and roast it. And the individual cloves pop right out after roasting!
Chicken stock. You can also use vegetable stock or vegetable bouillon.
Basil. Fresh basil has the best flavor. If you don't have fresh, you can use dried basil - but you only need about a third of the amount.
Heavy whipping cream. This gives the soup a smooth and creamy texture. For a dairy-free option, use a can of coconut cream instead.

See the printable recipe card for quantities and a complete list of ingredients.

How to Make Keto Tomato Soup

Step 1: Preheat and Prepare

Preheat your oven to 400°F.

Cut the tomatoes in half and place them on a baking sheet, cut side up. For easy cleanup, use a piece of parchment paper. Cut the onion into quarters and place them on the baking sheet.

A knife cutting the fresh tomatoes in half.

The onions on a baking sheet with the tomatoes.

Cut the top off the garlic bulb and place it on a small square of aluminum foil. Drizzle the tomatoes, onion, and garlic bulb with olive oil. Sprinkle with salt and pepper. Wrap the garlic bulb tightly in the aluminum foil.

The top of the garlic bulb being cut off with a knife.

The vegetables on the baking sheet drizzled with oil and seasoned with salt and pepper.

Step 2: Roast Away

Drizzle the tomatoes and onion with olive oil, season with salt and pepper, and roast everything for 25-30 minutes or until soft and the tops are starting to turn brown.

The roasted vegetables on a baking sheet.

Step 3: Blend the Roasted Vegetables

Once the roasted tomatoes, garlic, and onion are beautifully roasted, add them to a blender or large pot. Squeeze the garlic out of its skin and add it to the blender (or pot) along with the fresh basil.

A garlic clove being squeezed out of the garlic bulb.

Now it's time to blend! Blend until the ingredients are smooth. If you don't have a blender, you can use an immersion blender (as seen below), but it splatters quite a bit (a lot), so you have more of a mess to clean up.

You can also use a food processor, but you may need to do it in batches so it doesn't overflow. The blender was definitely the quickest and easiest.

An immersion blender blending up the roasted vegetables in a pot.

Fresh basil added to a blender with the roasted vegetables.

Step 4: Simmer with Broth

Once the ingredients are blended, pour the mixture into a soup pot or Dutch oven. Next, pour in the chicken or vegetable broth, and bring the mixture to a simmer over medium heat. Let it simmer for 10-15 minutes so the flavors meld together.

The blended vegetables in a large soup pot.

Chicken stock being poured into the soup pot.

Step 5: Cream it Up

Next, add the heavy cream and simmer for an additional 5 minutes until hot and steamy.

The heavy cream being poured into the tomato soup.

Step 6: Serve

Ladle your soup into bowls, and garnish with some fresh basil. You can also sprinkle on some Parmesan cheese if you like. And that's all there is to it! Season to taste with salt and black pepper if desired. Enjoy!

A bowl of creamy roasted garlic and tomato soup with a grilled cheese sandwich beside it.

Jeri's Top Tips

Use Ripe Tomatoes: The better your tomatoes, the better your soup will be.
Even Roasting: Cut the tomatoes and onion into similar sizes so they cook evenly.
Blending: If you like a chunkier texture, don't blend the soup as much. For a velvety smooth texture, blend longer. You can also strain the soup to remove any tomato skins that don't blend up.
Store Properly: If you have leftovers (lucky you!), store the soup in an airtight container in the fridge. It will keep for up to 3 days and makes a great quick meal.

Recipe FAQs

Can I use canned tomatoes instead of fresh?

Yes, you can use canned tomatoes if fresh ones are not available. Just be sure to drain all the liquid from the tomatoes, and cut whole tomatoes in half before roasting.

Can I make this recipe vegan?

Absolutely! Substitute the chicken broth with vegetable broth and the heavy cream with coconut cream.

Can I add other vegetables to the soup?

Yes! Roasted red peppers or carrots can add extra nutrition and flavor to this low-carb tomato soup recipe. Just be mindful of the additional carbs if you're following a strict low-carb diet.

The soup is too thick. How can I thin it?

If the soup is too thick for your liking, simply add more broth and adjust the seasoning as needed until you reach your desired consistency.

What can I serve with this soup?

A fresh green salad, low-carb crackers, or roasted vegetables make great sides for this soup. If you're not strictly low-carb, crusty whole-grain bread or grilled cheese sandwiches are delicious too!