Portobello Mushroom Soup Recipe

Melt butter in pot, add leeks and onion sauté 10 minutes. Add mushrooms sauté 5 minutes and reduce to low. Add flour and cook until thick about 3 minutes. Gradually stir in stock and sherry, bring to boil, reduce heat and simmer until thick about 10 minutes. Stir in half and half simmer 10 minutes. Add cayenne pepper and season with salt and pepper.