Creamy Keto Tomato Soup Recipe

This creamy keto tomato soup is rich, cozy, and simple to make with canned fire-roasted tomatoes, cream, pesto, and a few pantry seasonings. It gives you the comfort of classic tomato soup without sugar, flour, or cornstarch, making it an easy low-carb soup for lunch, dinner, or dipping with Keto Parmesan Garlic Bread Bites.

This keto tomato soup recipe comes together in one pot, then gets blended until smooth. Below, I’ll show you how to thicken tomato soup without flour, how to balance the acidity without sugar, and how to make it ahead for easy meals throughout the week.

Why You’ll Love This Keto Tomato Soup

• Creamy without flour or cornstarch: Xanthan gum helps thicken the soup while keeping it low-carb.
• Easy pantry-friendly recipe: Canned fire-roasted tomatoes keep the prep simple and add more flavor than plain canned tomatoes.
• Great for meal prep: This soup stores well in the refrigerator and freezer, so you can portion it out for quick lunches.
• Simple to customize: Keep it creamy with heavy cream, or use the dairy-free swaps below if you need them.
• Perfect for dipping: It pairs well with Keto Parmesan Garlic Bread Bites when you want that tomato soup and bread-style combo.

Ingredients in Creamy Keto Tomato Soup

Besides salt and pepper, this recipe uses a short list of simple ingredients:

• Fire-roasted tomatoes: I use canned fire-roasted tomatoes with their liquid to keep this recipe easy and full of flavor. Fresh roasted tomatoes can also work, but canned tomatoes make this soup much faster.
• Butter: Adds richness and helps soften the onions and garlic.
• Onion and garlic: These give the soup a savory base before the tomatoes go in.
• Water and concentrated chicken broth: Concentrated broth gives the soup deeper flavor. You can also skip the concentrate and use regular broth or bone broth in place of the water.
• Heavy cream: Makes the soup smooth and creamy.
• Pesto: Adds basil, garlic, oil, and Parmesan-style flavor without needing a long ingredient list.
• Italian seasoning: Rounds out the tomato flavor with dried herbs.
• Xanthan gum: Helps thicken the soup without flour or cornstarch. If you do not have xanthan gum, you can leave it out for a thinner soup or use unflavored collagen powder as noted in the recipe card.

How to Make Keto Tomato Soup

Build the flavor base

Start by softening the onions and garlic in butter. This quick step gives the soup a better base than simply simmering everything together from cold.

Simmer the tomatoes and seasonings

Add the fire-roasted tomatoes, pesto, Italian seasoning, broth concentrate, and water. Let everything simmer so the tomatoes soften and the flavors come together before blending.

Make it creamy and smooth

Stir in the cream, xanthan gum, and cheese, then blend the soup until smooth. An immersion blender keeps everything in one pot, but a regular blender also works. If using a regular blender, blend carefully in batches since hot soup expands.

Tips for the Best Low-Carb Tomato Soup

• Use fire-roasted tomatoes for more flavor: They add a deeper tomato taste without extra prep.
• Blend until smooth: This gives the soup that creamy tomato soup texture, especially when using canned tomatoes.
• Add xanthan gum carefully: A little goes a long way. Too much can make the soup gummy.
• Balance the acidity to taste: Tomatoes can be tangy, so a small amount of keto sweetener can help round out the flavor without adding sugar.
• Use broth for more depth: Regular broth or bone broth can replace the water and concentrated broth if that is what you have.

Are Tomatoes Keto?

Tomatoes can fit into keto and low-carb meals, but portion size matters. This recipe uses tomatoes in a way that keeps the soup low-carb while still giving you the classic tomato soup flavor. Each serving has about 7g net carbs.

How Many Carbs Are in Keto Tomato Soup?

This soup makes about 6 servings, with each serving being about 1 cup. Each serving has about 7g net carbs.

How to Thicken Tomato Soup Without Flour or Cornstarch

Traditional tomato soup is often thickened with flour or cornstarch. For this low-carb tomato soup, I use xanthan gum because it thickens the soup without adding carbs.

I also use xanthan gum in other recipes, including Keto Sweet Chili Sauce, Keto Raspberry Sauce, and several recipes in my Xanthan Gum Recipes collection. You can also see it used in sauces throughout my Keto Chinese Food Recipes.

If you do not have xanthan gum, you can leave it out for a thinner soup or swap 1/2 teaspoon xanthan gum with 1 tablespoon unflavored collagen powder.

How to Reduce Acidity in Tomato Soup

Tomato soup can taste sharp because tomatoes are naturally acidic. In traditional recipes, sugar is often used to balance that tangy flavor. To keep this tomato soup keto-friendly, you can add a small amount of keto sweetener and adjust to taste.

Dairy-Free Option

You can make this tomato soup dairy-free with a few simple swaps. Use full-fat coconut milk instead of heavy cream, leave out the cream cheese, and swap the butter for olive oil, coconut oil, or ghee. Coconut milk adds creaminess and a slight sweetness that works well with the tomato base.

Making Low-Carb Tomato Soup Ahead and Storing It

Refrigerator Storage

Store leftover soup in an airtight container in the refrigerator for up to 4 days.

Freezer Storage

You can freeze this soup for up to 4 months. I prefer freezing it in individual portions so it is easy to thaw for quick lunches or simple dinners.

What to Serve With Keto Tomato Soup

This soup is especially good with Keto Parmesan Garlic Bread Bites for dipping. You can also serve it with a simple salad or pair it with another low-carb comfort meal when you want something cozy but still easy.

More Keto and Low-Carb Soup Recipes

If you’re looking for more cozy low-carb soups from my kitchen, try these next:

• Keto Chicken Vegetable Soup: A simple one-pot soup with chicken, vegetables, and the comfort of chicken noodle soup without the noodles.
• Keto Taco Soup: A heartier option with taco flavor, ground meat, and easy toppings.
• Keto Cream of Mushroom Soup: Another creamy keto soup when you want something rich, savory, and low-carb.
• Low Carb Soup Recipes: Browse more keto and low-carb soup recipes from DrDavinahEats.

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