Banana Muffin Cookies

In a large bowl, beat together the butter and sugar until light and fluffy. Add the egg, milk, and vanilla to the mixture. Add in the banana. In a small bowl, whisk together the flour, baking soda, salt, and cinnamon. Add the flour mixture to the wet. Fold until combined. Cover bowl with plastic wrap and let it chill in fridge for at least 1 hour. To make the crumble: In a small bowl, stir together the flour, sugar, and cinnamon. Add in chunks of butter and rub together with your fingers until mixture looks like coarse crumbs. Set aside. Scoop out a ball of a dough using a cookie scoop and place onto a cookie sheet. Make an indent in the middle of the cookie either using the back of the cookie scoop or your fingers. Sprinkle some of the crumble (a little over a tablespoon) on top of the well. Repeat with the rest of the dough and crumble. Bake for 10-12 minutes at 350 F, or until slightly golden brown on the edges. Let it cool on the tray before transferring to a wire rack.