French Onion Soup

Peel and slice onions and put into a large pot with butter and saute until onions are soft, being careful not to burn. Add flour, Worcestershire sauce and then port sherry, stir. Add beef broth and water. Dash in salt, pepper and garlic powder. Cook on high until it boils, being careful so that it doesn't boil over. Put oven on broil and toast the bread. Put soup in oven-safe soup bowls, place a slice of toasted bread on top and top with mozzarella cheese and cook in oven until brown.