Preheat 350
Add a few more tbsp of cornstarch and completely cool before putting in the fridge or it gets too hard.
Bottom of pie crust, add 3 cut up bananas.
In medium saucepan combine sugar, flour/cornstarch, and salt. Gradually stir in milk. Cook and stir over medium heat till thickened and bubbly. Reduce heat; cook and stir 2 minutes more. Remove from heat. Separate egg yolks from whites. Beat egg yolks slightly. Gradually stir 1 cup of hot mixture into yolks. Return egg mixture to saucepan; bring to gentle boil. Cook and stir 2 minutes more. Remove from heat. Stir in butter and vanilla. Pour hot filling into baked pastry shell. Bake in oven for 12 to 15 min.