Banana Flips

1 (18.25 ounce) package yellow cake mix

1 (3.5 ounce) package instant banana pudding mix

4 eggs

1 ½ cups milk

1 ½ cups white sugar

¼ cup all-purpose flour

¾ cup butter

¾ cup shortening

¾ cup milk

1 ½ teaspoons banana extract

Preheat oven to 350 degrees F (175 degrees C). Grease and flour 2 - 9x13 inch pans.

In a large bowl, stir together the cake mix and instant pudding. Beat in the eggs and 1 1/2 cup of milk. Divide the batter evenly between the two pans.

Bake in preheated oven for 15 to 17 minutes, or until a wooden toothpick inserted into the cake comes out clean. While the cake is baking, make the filling.

Stir together the sugar and flour. In a medium bowl, cream together the butter, shortening and sugar mixture. Beat in the milk and banana extract until smooth.

When the cake is cooled, invert onto a serving tray. Spread filling over the top and cover with remaining layer of cake. Keep chilled until 1/2 hour before serving.