Preheat oven to 350F. Cream butter and sugar. Mix in egg and banana.
Stir together flour, baking powder, baking soda, salt, nuts and
chocolate chips. Add this mixture to creamed mixture alternately with
buttermilk. Stir until just blended. Pour batter into a greased and
floured loaf pan (9x5x3 inches). Bake for 65 minutes, or until bread
tests done. Cool in pan for about 5 minutes, then turn out on a wire
rack. Makes 1 loaf.