Preheat oven to 350°F and line a cookie sheet with parchment paper. In a large bowl, mash bananas and whisk with egg, olive oil, tahini, and vanilla until smooth. In a separate bowl, combine dry ingredients, then stir into the wet mixture until well combined. Add your mix-ins and stir thoroughly. Scoop dough onto the sheet (cookies won’t spread), flatten slightly with damp fingers, and bake for about 15 minutes until lightly browned. Let cool on a wire rack.
