"So sensational no one knows it is gluten-free, let alone pretty healthy. The richness of coconut sugar shines through into caramel caution! Too good to be true. The sweet crunchy topping is pure sin, to enjoy as do all my friends and family. This is a keeper. Delicious served warm with a non-dairy topping or more applesauce and a sprinkle of nutmeg."
Preheat oven to 350 degrees F (175 degrees C). Spray a 10x15-inch baking dish with cooking spray.
Place oats in the bowl of a food processor; pulse until finely ground. Place ghee in a microwave-safe bowl; cook in the microwave until melted, 15 to 30 seconds. Add ground oats, walnuts, 2/3 cup coconut sugar, 1 tablespoon coconut flour, 2 teaspoons cinnamon, and pinch salt to melted ghee; toss until coarse crumb mixture forms.
Combine gluten-free all-purpose flour, almond flour, 1 cup coconut sugar, flax seed meal, 2 tablespoons cinnamon, baking powder, baking soda, xanthan gum, ginger, pumpkin pie spice, 1 teaspoon sea salt, and cloves together in a large bowl.
Whisk applesauce, olive oil, eggs, honey, and vanilla extract together in a separate bowl. Add to flour mixture; mix well until thick batter forms. Pour batter into prepared baking dish. Top evenly with crumb mixture, pressing gently into batter.
Bake in preheated oven until a knife inserted into the center comes out clean, about 45 minutes. Cool in the pans for 10 minutes before transferring to a wire rack.