For the test, beat the egg with sugar, add soft butter, baking powder and flour. Knead well and knead the dough.
Lubricate the baking dish with a little oil and lay out the rolled dough forming the sides. Put the sliced bananas on the dough and place in the refrigerator.
Beat the egg with sugar, add sour cream and beat the flour again.
Pour the pie with the resulting cream and bake at 180 degrees for 20 minutes.
The banana pie is ready, you can serve both warm and cold.