Step 1

Space two oven racks so that the oven is divided into thirds. Preheat the oven to 350°F. Line two baking sheets with parchment paper.

Step 2

In a medium bowl, whisk together the flour, oats, cinnamon, nutmeg, baking soda and salt. Set aside.

Step 3

In the bowl of an electric mixer, cream the butter, granulated sugar and brown sugar until light and fluffy, a few minutes. Scrape down the sides of the bowl and add the egg, mashed bananas and vanilla extract; beat until combined. Add the flour and oats mixture and mix on low speed until well combined. Do not overmix. The batter will be wetter than most cookie doughs; that's okay.

Step 4

Scoop large balls of dough (about 1½ tablespoons) onto the prepared baking sheet, spacing at least 3 inches apart, as they spread quite a bit (I use a small ice cream scooper with a wire scraper). Bake for 14-17 minutes, rotating the pans from top to bottom and front to back midway through, until golden brown. Cool on the baking sheet for a few minutes, then transfer to a wire rack to cool completely. Repeat with remaining cookie dough.

Step 5

Freezer-Friendly Instructions: The Cookie Dough can be Frozen for up to 3 Months: Roll the dough into balls, let set on a baking sheet in the freezer, then place in a sealable bag and press out as much air as possible. Bake as needed directly from the freezer. (Allow 1 to 2 minutes longer in the oven.) To Freeze After Baking: Let the cookies cool completely and store in an airtight container separating layers with parchment paper or aluminum foil. Before serving, remove the cookies from the container and let them come to room temperature.