Preheat oven to 350°F. Prepare 2 cookie sheets with parchment paper.
Mix all dry ingredients in a large bowl. Set aside.
Place banana pieces into blender and mix until pureed and no lumps. Add vanilla and pulse to mix. Scrape all the banana mixture into the dry ingredients and mix well. Batter will be wet.
Using a heaping teaspoon, scoop out batter and place on cookie sheets. You will have to form the batter into uneven bites.
Bake 15-20 minutes or until browned. Cool on cookie sheet, then transfer to covered container and refrigerate. These also freeze well.
Variation: 3 bananas and 1/2 cup peanut butter. Add bananas and peanut butter to blender and mix until well pureed.