Preheat oven to 325º. Mash bananas in a large bowl. Add flour, sugar, baking soda, salt, and egg.
Melt butter in microwave, add it to the bowl, and stir until just blended.
Pour into greased loaf pan. Sprinkle on chocolate chips. Bake for 70 minutes, or until a toothpick inserted in middle comes out clean.