Mix cornstarch, sugar, and salt in a 3 quart saucepan.
Add milk and cream and cook over medium heat until smooth and thick, stirring constantly.
Pour small amount of hot mixture into egg yolks; blend thoroughly.
Pour back into saucepan.
Cook another 2 or 3 minutes.
Remove from heat and add butter and vanilla.
Coconut Cream Pie: Add 1/2 cup coconut (toasted, if desired) to pie filling. Pour into baked shell. Chill 3 to 4 hours. When ready to serve, whip the cream and spread over pie. Top with another 1/2 cup coconut.
Banana Cream Pie: Slice 2 bananas into pie shell. Pour the filling over the bananas. Chill 3 to 4 hours. When ready to serve, whip cream and spread over pie.
Chocolate Cream Pie: Decrease sugar in pie filing to 3/4 cup. Add 1/2 cup chocolate syrup to cooked mixture. Or use the full cup of sugar and 1/2 cup melted chocolate chips. Pour into pie shell. Chill 3 to 4 hours. When ready to serve, whip cream and spread over pie. Makes 6 servings.
2 whole eggs may be used, but filling may not be as smooth.