Preheat oven to 325°F (163°C). Line 2 large baking sheets with parchment paper or silicone baking mats. Set aside.

Place all of the ingredients in a large bowl. (I usually mash the bananas in a large bowl, and then add the remaining ingredients.) Stir everything together until fully combined, or use a handheld or stand mixer with a paddle attachment to beat. The dough is thick and heavy.

Using a 1/4 cup measuring cup, portion 1/4-cup mounds of cookie dough (about 70g each) onto prepared cookie sheet. Use the back of a spoon to slightly flatten out into a cookie shape. (The cookies will not spread in the oven.)

Bake for 17–20 minutes or until the edges are lightly browned. Cool cookies on the baking sheets for 10 minutes, then transfer to a wire rack to cool completely.

Cover leftover cookies and store at room temperature for up to 2 days or in the refrigerator for up to 10 days. Cookies get extra soft in storage, and taste best right out of the refrigerator.