Prep your air fryer: Preheat to 325°F (160°C) for 3–5 minutes. Line the basket with a perforated parchment sheet or lightly spray with oil.

Mash the banana: In a large bowl, mash 1 ripe banana until smooth. You want about 1/2 cup.

Add wet ingredients: Stir in 1/3 cup unsweetened applesauce, 1/4 cup creamy peanut butter, 1/4 cup maple syrup, 1 egg, and 1 teaspoon vanilla. Mix until well combined.

Whisk dry ingredients: In a separate bowl, combine 1 1/2 cups rolled oats, 1/2 cup oat flour, 1 teaspoon baking powder, 1 teaspoon cinnamon, and 1/4 teaspoon salt.

Combine wet and dry: Fold the dry ingredients into the wet mixture until just combined. The batter will be thick and scoopable, not pourable.

Add mix-ins: Stir in 1/3–1/2 cup of your choice—raisins, chocolate chips, chopped walnuts, sunflower seeds, or a mix. Don’t overload; too many add-ins can prevent even cooking.

Portion the cookies: Use a medium cookie scoop or heaping tablespoon to form balls. Flatten gently with your fingers into 1/2-inch-thick rounds. Aim for uniform size for even cooking.

Arrange in the basket: Place cookies in a single layer with a little space between them. Work in batches if needed; crowding leads to soggy edges.

Air fry: Cook at 325°F (160°C) for 8–10 minutes. Check at 8 minutes. They’re done when the edges are lightly golden and the centers feel set but still soft.

Cool briefly: Let cookies rest in the basket for 2–3 minutes, then transfer to a rack to cool. They firm up as they cool.

Repeat: Finish remaining batter. If your air fryer runs hot, reduce time by 1–2 minutes for later batches.