Yacht club gallery - Disney's yacht club resort Serves 4 3 large spanish onions 4 tb spoons butter 4 tb spoons flour 2 cups milk 2 cups of chicken stock or broth 1/2 tsp salt 1/2 tsp pepper 1/2 tsp mace 1 egg yolk beaten 1 cup grated mild cheddar cheese melt butter in a 4-quart sauce pot on medium heat. Add onions and saute until lightly browned. Add flour and cook for 5 minutes until butter and flour are well blended. Slowley add milk and chicken stock, stiring constantly to prevent lumps. Season with salt, pepper and mace, continue to cook until soup thickens. Wisk in the egg yolk slowly and add the grated cheese. Simmer for another 5 to 10 minutes, stirring occasionally to prevent burning. Remove from heat and serve immediately.