Serves 6.
2 Tbsp olive oil
1 Tbsp butter
1 large onion, peeled and diced
1 large clove garlic, peeled and smashed
2 Tbsp unbleached all-purpose flour
2-1/2 cups homemade or low-sodium chicken stock (I like Swanson 99%)
26-oz box Pomi chopped tomatoes (or other good quality chopped tomatoes, with their juice)
1 tsp sugar or 1 packet sugar substitute
1-1/2 tsp dry thyme leaf or 1 sprig fresh thyme
2 Tbsp tomato paste
A pinch of mild red pepper flakes (or more, to taste)
Kosher salt and fresh black pepper, to taste
Additional
fresh thyme, basil, chives, dill or parsley, for garnish (I used some
chopped scallions, but herbs would be better. I didn't have any on
hand.)
In a 3-4 quart Dutch oven or heavy non-reactive stock pot, heat the olive oil and butter over medium-low heat. When the butter melts, add the onion and garlic, and cook, stirring occasionally, until the onion is softened but not brown (5-6 minutes). Add the flour, and stir for one minute, until the flour coats the onions.
Add the broth, tomatoes, sugar, thyme, tomato paste, red pepper flakes, and a pinch of salt and pepper. Raise the heat to medium-high, and cook, stirring, until the soup is lightly thickened, 2-3 minutes. Reduce heat to low, cover, and simmer the soup for 30 minutes. Discard the thyme sprig, if using fresh thyme. Taste the soup and add salt and pepper to taste. Remove from heat, and let the soup cool for 15 minutes.
Using an immersion blender (or in batches in a standing blender), puree the soup to desired consistency. Again, taste for seasoning. Reheat if needed before serving, or allow to cool completely and refrigerate. Just before serving, garnish with fresh herbs.