How to Make It
Preheat oven to 350° F. Lightly coat an 8-inch square baking pan with cooking spray, and line with parchment paper, leaving a 2-inch overhang on all sides. Stir together 1 cup of the walnuts, 1 tablespoon of the maple syrup, and ¼ teaspoon of the salt in a medium bowl. Set aside.
Stir together flours, baking powder, and remaining ½ teaspoon salt in a large bowl. Place coconut oil in a separate microwavable bowl, and microwave on HIGH until melted, about 30 seconds. Whisk in squash, eggs, vanilla, and remaining ¾ cup maple syrup until thoroughly combined. Add dry ingredients to squash mixture, and stir just until incorporated; fold in remaining ½ cup walnuts. Spoon batter into prepared baking pan, and sprinkle reserved maple walnuts over top. Bake in preheated oven until set and blondies spring back when pressed lightly in the center, 30 to 35 minutes. Let cool 10 minutes on a wire rack, and cut into 16 squares.