Mix almond flour, coconut flour, baking powder, and salt in a bowl.
In another bowl, whisk together eggs, erythritol, melted butter, and vanilla extract.
Add the wet ingredients to the dry ingredients and combine with a spatula to form a dough.
Flatten the dough to 2-3 cm thickness and cut into triangles.
Bake in a preheated oven at 180°C for 20 minutes.
Cool on a wire rack, then serve immediately or store.