2 1/2 c. rhubarb, cut in 1/2-inch pieces
1 egg, beaten
1 c. sugar
2 1/4 tbsp. quick-cooking tapioca
4 tsp. butter
Pastry for 9 to 10-inch two-crust pie

Prepare rhubarb and set aside. Combine remaining ingredients to form paste and add to rhubarb. Spoon into unbaked pie shell. Bake at 400 degrees for 20 minutes, then 350 degrees for 45 minutes.