Introduction
Tomato soup is a comforting classic that’s both simple to prepare and delicious. With just five ingredients, this 5 Ingredient Tomato Soup recipe uses the rich flavor of San Marzano tomatoes enhanced by butter and onions. Whether you’re having a cozy night in or looking for a quick meal, this soup is perfect for any occasion.
Detailed Ingredients with measures
– two 28-ounce cans San Marzano tomatoes (whole or crushed)
– 1 stick (8 tablespoons) salted butter
– 1 yellow onion, peeled and cut into 4 chunks
– 3–4 cloves smashed garlic (optional)
– 1 1/2 teaspoons salt
Prep Time
15 minutes
Cook Time, Total Time, Yield
Cook Time: 45 minutes
Total Time: 1 hour
Yield: Serves 4-6
Instructions
Make the Tomato Soup: Put the tomatoes, butter, and onion in a large saucepan or Dutch oven. Bring it up to a low bubble, then turn the heat to medium low. Cover partially with a lid; let it simmer for 45 minutes, stirring every 15 minutes to prevent scorching on the bottom.
Remove Onion Chunks: After simmering, use tongs to remove the onion pieces. You can leave the garlic in for added flavor, but this is a personal choice.
Blend the Tomato Soup: Use an immersion blender to blend the soup to your desired consistency. Taste and adjust seasoning; you can thin it out with milk, water, broth, or cream if needed.
Serve: Enjoy the tomato soup with your favorite sides like garlic bread, grilled cheese, croutons, or crackers.
Notes
To make this in the Instant Pot: Simply place all ingredients in the pot, cook for 20 minutes, and release the pressure. Remove the onion chunks and blend. This method is hands-off and prevents burning, but the stovetop version often has a slightly richer and sweeter flavor due to caramelization. Both methods yield a delicious result!
Detailed Directions and Instructions
Prepare the Ingredients
Gather two 28-ounce cans of San Marzano tomatoes (whole or crushed), 1 stick (8 tablespoons) of salted butter, 1 yellow onion cut into 4 chunks, 3-4 smashed garlic cloves (optional), and 1 1/2 teaspoons of salt.
Combine Ingredients in a Pot
Place the tomatoes, butter, onion chunks, and garlic (if using) in a large saucepan or Dutch oven.
Start Cooking
Heat the mixture over medium-low heat until it reaches a low bubble.
Simmer the Soup
Partially cover the pot with a lid and let it simmer for 45 minutes. Stir the soup every 15 minutes to prevent it from scorching on the bottom.
Remove Onion Chunks
After simmering, use tongs to remove the onion pieces from the pot. You may leave the garlic in for additional flavor.
Blend the Soup
Use an immersion blender to blend the soup until it reaches your desired smoothness. Taste and adjust the consistency, adding milk, water, broth, or cream as preferred.
Serve the Soup
Serve the tomato soup hot with accompaniments like garlic bread, grilled cheese, croutons, crackers, or pesto.
Notes
Instant Pot Method
To make this soup in the Instant Pot, add all ingredients into the pot and cook on high pressure for 20 minutes. Release the pressure, remove the onion chunks, and blend the soup. This method allows for a more hands-off approach, reducing the risk of burning.
Flavor Consideration
While both the stovetop and Instant Pot methods yield delicious soup, the stovetop version can provide a slightly sweeter and richer flavor due to increased caramelization.

Cook techniques
Simmering
Simmering is a gentle cooking technique where you heat the mixture just below boiling point. This method helps to meld flavors and allows for gradual cooking without burning.
Removing Onion Chunks
After simmering, it’s important to remove the onion chunks for a smooth soup texture. Using tongs makes this task easy and ensures you retain the flavor imparted by the onion.
Blending
Blending the soup can be done using an immersion blender for convenience. This technique allows for control over the soup’s texture, achieving smoothness according to your preference.
Adjusting Consistency
You can adjust the soup’s consistency by adding milk, water, broth, or cream. This technique enables you to customize the soup to your liking, making it richer or lighter as desired.
Instant Pot Method
Using an Instant Pot allows for a more hands-off approach to cooking the soup. Everything cooks under pressure, making it a quick option with minimal supervision.
FAQ
Can I use fresh tomatoes instead of canned?
Yes, fresh tomatoes can be used, but they may require peeling and additional cooking time to achieve the same rich flavor.
What’s the purpose of adding butter?
Butter adds richness and depth to the soup, enhancing the overall flavor profile.
Is it necessary to use San Marzano tomatoes?
While San Marzano tomatoes are known for their quality and sweetness, you can use other canned tomatoes. Just be mindful that the flavor may vary.
Can I add other ingredients?
Yes, you can customize the soup by adding herbs, spices, or vegetables to suit your taste.
How should I store leftovers?
Leftover tomato soup can be stored in an airtight container in the refrigerator for up to 5 days or frozen for longer storage.
Conclusion
The 5 Ingredient Tomato Soup is a delightful and simple recipe that celebrates the robust flavors of San Marzano tomatoes and buttery goodness. Perfectly cooked and blended, this soup serves as a comforting dish on its own or an excellent base for various creative pairings. Whether opting for the stovetop or Instant Pot method, the outcome remains rich and satisfying, making it an ideal choice for both busy weeknights and leisurely weekends.
Grilled Cheese Sandwich
Pairing your tomato soup with a classic grilled cheese sandwich is a timeless combination. The melty cheese and crispy bread add a delicious contrast to the smooth soup.
Garlic Bread
Serve with toasted garlic bread for a flavor-packed addition. The crunchy, buttery bread, infused with garlic, complements the soup perfectly.
Croutons
Top your soup with homemade or store-bought croutons for added texture. They provide a delightful crunch that enhances each spoonful of soup.
Pesto Swirl
Add a swirl of fresh basil pesto to each bowl of soup before serving. This not only enhances the flavor with a burst of basil but also adds a beautiful presentation.
Cheddar Cheese Crumbles
Sprinkle sharp cheddar cheese crumbles on top for an extra layer of flavor that melds beautifully with the soup’s richness.
Fresh Herbs
Garnish with fresh herbs like basil or parsley for a fresh aroma and vibrant color. The herbal notes bring a new depth to the overall flavor.
Avocado Toast
Enjoy your soup alongside a slice of avocado toast. The creamy avocado adds a healthy fat and subtle flavor that pairs well with the acidity of the tomatoes.
Spicy Chili Flakes
For a kick, sprinkle some chili flakes over the soup before serving. This adds a delightful heat that can elevate the dish for those who enjoy a spicy touch.

