French Onion Soup

Slice onions paper thin.

Fill large pot to the top with onions.

Add 1/4 cup of butter and simmer on low until onions are translucent.

Mix in 1 teaspoon of dry mustard, salt and pepper. Add equal amounts of beef and chicken stock and 1/4 cup of sherry. Cook on low (without boiling) for 6 to 8 hours a day, for two days. Add sherry to replace fluid as it evaporates.

Cut French bread into thin slices and place on a baking sheet.

Bake in oven on low temperature for 3 to 4 hours, until hard.

Grate Gruyere cheese on bread and continue baking for 1 hour.