Preheat oven to 350°F (175°C) and line a baking sheet with parchment paper. Tip: For extra crispiness, lightly grease the parchment paper.

In a large bowl, mix rolled oats, hazelnut flour, protein powder, baking powder, and salt until combined. Tip: Sift dry ingredients to avoid clumps.

Add maple syrup, almond butter, and vanilla extract. Stir until a thick dough forms. Tip: If the dough is too dry, add 1-2 tbsp of water.

Fold in chopped hazelnuts (if using). Tip: Toast hazelnuts first for deeper flavor.

Scoop 1.5 tbsp of dough per cookie onto the baking sheet. Flatten slightly with a fork. Tip: Wet the fork to prevent sticking.

Bake for 10-12 minutes until edges are golden. Let cool for 5 minutes before serving. Tip: Cookies will firm up as they cool.