Preheat your oven to 350°F (175°C). Grease a 9×9-inch baking dish or line with parchment paper.

Blend the cottage cheese until silky smooth with no lumps.

Peel, core, and slice the apples. Toss them in a bowl with cinnamon, nutmeg, and maple syrup. Set aside.

In a bowl, combine almond flour, rolled oats, baking powder, and protein powder (if using). Whisk to evenly distribute the protein powder.

In another bowl, combine blended cottage cheese, Greek yogurt, melted butter, and vanilla extract. Stir gently until smooth and combined.

Add dry ingredients to wet mixture. Fold gently with a spatula until just combined. Do not overmix.

Spread the apple mixture evenly in the baking dish. Dollop the protein crumble topping over the apples and spread evenly.

Bake for 40-45 minutes until the topping is golden brown and the apples are bubbling. Check at 40 minutes to avoid overbaking.

Let the crumble cool for 10 minutes before serving to help the topping set.