Preheat oven to 375°F.

Sift flour, baking powder, soda, and salt together, set aside.

Cream shortening and sugar. Add eggs and bananas. Mix in buttermilk and vanilla.

Add flour mixture alternately with wet ingredients beginning and ending with flour.

Grease and flour 2 9 inch layer pans and pour in batter. Bake 25 to 30 minutes.

For Frosting

Heat milk until very hot but not boiling.

Cream butter and shortening. Gradually add cornstarch and sugar.

Beat well after each addition, then add vanilla.

Add hot milk to sugar mixture a little at a time, beating though my after each addition until all sugar dissolves and thick enough to spread

Make sure to add milk a little at a time to make sure frosting doesn't curdle!!!