Prep: Preheat the oven to 350F. Line a baking sheet with parchment paper or a silicone baking mat and set aside. Pat your blueberries dry with a clean kitchen towel of paper towels if you have just washed them
Wet Ingredients: Add the applesauce, maple syrup, almond butter, and vanilla (if using) to a large mixing bowl. Use a whisk to mix well, until the almond butter and applesauce are evenly combined.
Dry Ingredients: Add the oat flour, almond flour, ground flax, baking powder, cinnamon (if using), and salt to the bowl and mix well, until a thick batter forms. Add the rolled oats and blueberries and use the spatula to gently fold them into the batter, until combined.
Form “Muffin Tops”: Use either a 1/3 cup cookie scoop or 1/3 measuring cup and spatula to scoop a heaping 1/3 cup “cookie” out of the batter, then place it on the prepared baking sheet without flattening it. Repeat with the remaining batter; you should have 8 medium cookies. (Tip: the cookie scoop makes the best muffin-like balls, but you can also use slightly damp fingers to re-shape your cookies if you use the measuring cup method instead)
Bake: Bake in the middle rack of the oven for 22 to 25 minutes, until the cookies have spread and the outer edges of the cookies are just slightly brown.
Cool: Remove from the oven and let the cookies rest on the baking sheet for 20 minutes, to firm up. Then, use a firm spatula to transfer them to a wire rack and let cool completely.
Serve & Store: Serve immediately, or store any leftovers in an airtight container in the refrigerator for up to 5 days, or freeze for up to 2 months and thaw when the craving strikes :) Reheat thawed cookies in the toaster oven for a few minutes for the best crispy edges and texture!