5 tablespoons butter
1 tablespoon vegetable oil
1 cup chopped onions (2 small-to-medium onions)
28-ounce can tomato purée or tomatoes in purée
1/2 teaspoon basil
1/4 teaspoon thyme
a couple of shakes black pepper
3 tablespoons King Arthur Unbleached All-Purpose Flour
1 can (a scant 2 cups) chicken broth
1/4 teaspoon baking soda
1 to 3 tablespoons sugar, to taste
1 1/2 cups evaporated milk
1/2 teaspoon salt
- In a large saucepan, heat the butter and vegetable oil over medium heat. Add the onion and sauté until softened and golden, about 10 minutes.
- Add the tomatoes, basil, thyme, and black pepper. Bring the mixture to a simmer, and cook for 10 minutes.
- In a small bowl, combine the flour and broth, whisking until smooth, and add this mixture to the soup, stirring constantly.
- Cover and simmer slowly for 25 minutes, stirring occasionally.
- If you've used diced tomatoes, purée the soup in a blender or food processor, or use a hand blender. If you've used tomato purée, there's no need to blend; the onion bits will give the soup a bit of body.
- Return the soup to the stove, and set it on a burner over low-to-medium heat.
- Stir in the baking soda (the soup will foam up briefly; don't worry, but be sure it's in a big enough pot), the sugar, milk, and salt. Heat to a bare simmer, stirring constantly.
- Serve hot.