I've never used pudding in my filling. This is my mother's very delicious recipe. It does require you to stand at the stove to stir while cooking:
3/4 cup brown sugar
4 tbsp cornstarch
1/2 tsp salt
2 cups milk
2 beaten egg yolks
1 tbsp butter
1 tsp vanilla
9" baked pie shell
Stir brown sugar, cornstarch, salt, and milk in saucepan over medium heat until thickened. Stir in egg yolks until thickened.
Take off heat and stir in butter and vanilla. Pour into baked crust and bake at 400 degrees until brown, about 5 minutes.