1/2 cup butter
10 slices sourdough bread
6 ounces sharp Cheddar cheese, grated
2 cups milk
3 egg yolks
1/2 teaspoon salt
1/2 teaspoon dry mustard
1/2 teaspoon cayenne pepper
2 dashes Worcestershire sauce
3 egg whites

In a large saucepan over medium heat, melt butter; add diced slices of bread, stirring until coated. Add grated Cheddar cheese; stir well. Set aside.

In a medium bowl, with a wire whisk combine milk, egg yolks, salt, dry mustard, Worcestershire sauce and cayenne pepper; beat well. Pour over the bread cubes.

In another bowl beat egg whites until stiff, but not dry; fold into bread mixture, toss until mixed. Spoon into a lightly greased 9-inch square baking dish. Cover and chill overnight.

Bake, uncovered, at 325 degrees F for 30 minutes, or until the center is set.

Serves 6.