In another medium-sized mixing bowl, mix butter, sugar, light brown sugar, vanilla extract, and bananas. It is normal if you can still see tiny butter pieces. They will melt when the cookies bake.
5 tablespoons unsalted butter, 1/4 cup granulated sugar, 1/4 cup light brown sugar, 2 teaspoons vanilla extract, 3/4 cup mashed overripe bananas
Mix in the egg.
1 large egg
Add the dry ingredients to the wet ingredients a little at a time until just combined.
Gently fold in chocolate chips.
1 cup dark chocolate chips
Scoop tablespoon-sized balls of dough two inches apart from each other onto an ungreased cookie sheet.
Bake until golden brown, about 12 minutes.
Transfer to a cooling rack to cool completely.
It is super important that the bananas in this recipe be not just ripe, but overripe (practically black). If they aren't quite overripe, microwave them in 30 second intervals until they are really soft. This will help to bring out the sweetness.Keep the banana cookies at room temperature in an airtight container for 3 days, in the refrigerator for 1 week, or in the freezer for months.