Preheat oven to 350 degrees.
Mash the bananas and grate the zucchini, squeezing out extra liquid, and set aside.
In a medium bowl, add the flour, sugar, soda, baking powder, salt and cinnamon, and stir.
Add the butter, milk, eggs, extract, bananas and zucchini, and mix well.
Stir in chocolate chips
Spoon batter into a lightly greased muffin pan. I filled all 12 cups to the brim, and this produced some nice monster muffins.
Add extra chips to the tops of the muffins, if you like, and bake for about 20 to 25 minutes, or until tops are firm and a toothpick comes out clean from the center of the muffins.