Mix sugar, egg and corn starch together, put aside. Bring milk to a boil, Add a small amount of hot milk to egg mixture. Stir well. Add this mixture to the hot milk, stirring constantly. Stir in vanilla and butter. Mix well. Pour mixture into tart crust and bake in 324 degree oven for 25 to 35 minutes.

You can also use this custard in another awesome recipe.
You will need a small angel food cake and 3 or 4 bananas.
Directions:
Cut the angel food cake into bite size pieces and put them in a large casserole dish. Slice the bananas into the dish. Gently mix the two. Pour warm pudding over this mixture. I like it best served warm. Put the remaining pudding into the refrigerator. Some prefer it cold. Any way you eat it is a treat.