Trim crust off bread. Save crust for another use.

Spread butter each side of the bread with the margarine.

Place a layer bread in the bottom of a 9 x 13 pan, just enough buttered slices to cover the bottom of the pan.

Then layer 1 cup of the cheese, half the ham, and half the green onion.

Place another layer of buttered bread slices.

Top with 1 cup cheese, remaining ham, and remaining green onion.

In a bowl, beat egg, milk, salt, paprika, and mustard together. Pour over layers in pan.

Top with remaining cheese and refrigerate overnight.

In the morning, bake at 350 degrees for 45-60 minutes, until knife comes out clean. Serves 9-12