This is a classic tomato soup recipe and this version is better than you remember it to be. The secret is brown butter.
- 4 tablespoon unsalted butter divided
- 2 tablespoon olive oil divided
- 1 medium onion peeled and thinly sliced
- 4 clove garlic peeled & lightly smashed
- 2 (28 oz) cans san marzano tomatoes
- 1 cup water
- 1 cup cream
- ½ teaspoon kosher salt plus more as needed
- ¼ teaspoon freshly cracked black pepper
- ¼ teaspoon crushed red pepper
- ¼ teaspoon celery seeds
- ¼ teaspoon dried marjoram
- 1 tablespoon sugar
- 3 slice rustic bread rusts trimmed, cut into ½‑inch cubes
Heat 1 tablespoon butter and 1 tablespoon olive oil in a large Dutch oven set over medium heat; sauté the onion and garlic until translucent and just beginning to color, about 8 minutes. Add the tomatoes with the juice, water, cream, salt, pepper, red pepper, celery seeds, marjoram, and sugar. Raise the heat to medium high and bring to a boil, then turn the heat to low and simmer for 15 minutes. Remove from the heat and use an immersion blender to purée until completely smooth. Return the soup to low heat and simmer 20 more minutes.
Meanwhile, make the brown butter and croutons. Heat a large, heavy bottomed sauté pan over medium heat. Add the 3 tablespoons remaining butter. As it begins to melt, start swirling the pan frequently and watching the butter carefully. You will notice the butter will get foamy, and then the milk solids will begin to brown. Once that starts, remove skillet from heat. Smell the butter; it should have a nutty aroma, and be caramel in color. Stir about 2/3 of the brown butter into the soup. Set the rest aside. Season the soup with more salt and pepper to taste
In a separate sauté pan, heat the remaining 1 tablespoon oil over medium high heat. Add the bread cubes and toast, stirring occasionally, until golden, about 6 to 8 minutes. Remove from the heat and toss with remaining browned butter until absorbed.
Serve the soup garnished with the croutons.