BLT Creamy Soup

In a 3-quart pot, cook the bacon over medium heat until lightly browned. Add the onions and cook about 4 minutes, until wilted. Add the butter, stir until melted. Sprinkle the flour into the pot, then stir it in until well blended. Add hot chicken broth, tomatoes, nutmeg and cayenne pepper. Add the lettuce and stir to wilt. Heat the soup to boiling, stirring constantly, then reduce the heat and simmer gently for 5 minutes. Add the cream and mix well. Add a pinch of salt and pepper, plus an additional tablespoon of butter. Mix together the mayonnaise and sour cream. Serve each portion with a dollop of mayonnaise mixture topped with crumbled bacon.