This recipe is an adaptation of Marcella Hazan's Tomato Sauce with Onion and Butter. When I first made her tomato sauce recipe I blended it after it finished cooking since my kids don't like chunks of tomato in their sauce. The next day I dipped some bread in the reheated leftovers and thought, this would make a great soup! After two rounds of testing, this is what I came up with. For the soup version, I added some carrot, celery, and garlic for more flavor and then topped it with some croutons, basil, and parmesan when it was finished. This soup is simple but flavorful and would be perfect with a grilled cheese sandwich. —Bridgette
Add the tomatoes to a medium dutch oven. Using your hands or the back of a spoon, break up the whole tomatoes into smaller chunks.
Add the onion, butter, carrot, celery, garlic, and salt to the tomatoes. Stir to combine.
Cook the soup on the stove over medium heat until the butter is melted. Cover the dutch oven with a lid and transfer it to the oven. Braise the soup in the oven until the carrots have softened, about 45 minutes.
While the soup is braising, make the croutons. Heat 3 Tbsps of olive oil in a large skillet over medium heat. Add the torn bread pieces and season them with salt.
Toast the bread in the olive oil, stirring frequently, until all the pieces are golden brown and crispy. Remove from the heat and set aside
When the carrots are softened, use either an immersion blender or a regular blender to puree the soup. The immersion blender will leave the soup with a little more texture than a regular blender.
Taste and adjust the salt if necessary
Top the soup with the croutons, basil, and grated parmesan just before serving.