Beat the butter with the sugar and vanilla extract until light and fluffy. Add the eggs, one at a time and beat until well incorporated. Add the sifted dry ingredients in 3 additions, alternately with the banana mixture in two additions, beating only until blended. Fold in the chocolate morsels.

Line muffin tins with cupcake papers or used greased nonstick muffin tin. Fill each cup about 3/4 of the way with batter and bake at 350°F for 30 minutes. Cool for 5 minutes before removing from tins.

Makes 18 muffins.