Red lentils are common in Turkish, Indian, and Eastern European dishes and cook in half the time of green or brown lentils. They can be found in Indian and Middle Eastern grocery stores or alongside other dried beans in natural-foods supermarkets. You can also flavor this soup with curry powder, dried thyme, or paprika in place of the ground cumin.
1. Heat oil in large saucepan over medium heat. Add onion and garlic, and sauté 5 minutes, or until soft. Stir in red lentils and cumin, and cook 1 minute, or until cumin is fragrant and lentils are coated with oil. Stir in tomatoes with liquid, honey, bay leaves, and 7 cups water. Season with salt and pepper, and bring to a boil.
2. Cover pan, reduce heat to medium-low, and simmer 20 minutes, or until lentils are soft and falling apart, and soup is thick. Add a little water to thin soup, if necessary. Remove bay leaves, stir in vinegar, and serve with dollops of yogurt.