Preheat the oven to 375°F (190°C). Use a chef's knife to peel, core, and slice the apples into thin pieces. Place the sliced apples in a mixing bowl and sprinkle with cinnamon and sweetener, then toss to coat evenly. Transfer the seasoned apples into a baking dish.
In a separate bowl, combine almond flour, chopped nuts, and then add the cold butter or coconut oil. Use a pastry cutter or your fingers to work the fat into the dry ingredients until the mixture resembles coarse crumbs. Spread the crumb topping evenly over the apples in the baking dish.
Place the baking dish in the preheated oven and bake for approximately 20 minutes, or until the topping turns golden brown and crispy. The apple filling should be bubbling around the edges. Smell the warm aroma of cinnamon and baked fruit.
Remove the apple crisp from the oven and let it cool slightly. The topping should be visibly crisp and golden, while the apples should be tender and caramelized. Serve warm, optionally garnished with a dollop of whipped cream or a sprinkle of extra nuts.
Slice a portion and observe the contrast between the soft, caramelized apple layer and the crunchy topping. The dish should have a warm, inviting appearance with a crispy topping and tender fruit inside.
