Preheat the oven to 350 degrees. Spray a mini muffin tin with cooking spray.

In a medium mixing bowl, whisk the maple syrup, applesauce, coconut oil, egg, and vanilla extract. (If your maple syrup or applesauce is chilled, microwave or warm on the stove until room temperature/slightly warm or it will cause the coconut oil to solidify.) In a separate bowl, combine the oats, flour, cinnamon, baking soda, and salt.

Add the dry ingredients to the wet ingredients and stir just until incorporated. Fold in the zucchini and walnuts.

Fill each well of the mini muffin tin about three-quarters full with batter. (I like to use a 2 tablespoon cookie scoop for this.)

Bake for 15 minutes or until a tester inserted into the center of a muffin comes out clean.

Let the muffins cool in the tin for 10 minutes. (This is essential! If you try to remove them sooner, they will crumble.) Run a butter knife around each bite to loosen it, then transfer to a cooling rack to cool completely.