This is a warming, hearty soup, and the flavor of the roasted red peppers really comes through in every bite. If you want a version that's less brown, try red lentils (they also cook faster, but don't have quite the same comforting heartiness of their brown cousins).
2 cups brown lentils
7-8 cups beef stock and/or water
4-6 cloves garlic, minced
1 medium onion, chopped
1 medium fennel bulb, cored and chopped
5-6 ounces roasted red peppers, chopped (~3 medium peppers)
2 Tbsp red wine vinegar
Salt and pepper
Place the lentils in a soup pot with 6 cups of water. Bring to a boil, then simmer until tender, about 30 minutes.
While the lentils cook, heat a little olive oil in a large skillet. Add the garlic, onion, and fennel, and saute over medium heat, stirring frequently, until soft, about 10 minutes. Add the roasted roasted red pepper and set aside.
When the lentils are tender, stir in the vegetable mixture and the red wine vinegar. Puree using an immersion blender or carefully do it in batches in a regular blender. Add salt and pepper to taste.
Variation: Substitute red lentils, chicken or vegetable stock, and white wine vinegar or sherry vinegar for a lighter texture and flavor.