Preheat oven to 350°F (175°C) and line a baking sheet with parchment. Whisk almond flour, coconut flakes, flax meal, cinnamon, baking powder, and salt in a bowl.

Cream butter and sweetener with an electric mixer on medium until fluffy, about 2 minutes.

Beat in the egg and vanilla on low until smooth, about 30 seconds.

Stir the dry mixture into the wet with a spatula until a thick dough forms. Fold in pecans if using.

Scoop rounded tablespoons of dough onto the sheet, flatten slightly, and bake 10 to 12 minutes until edges are golden. Cool on the pan 5 minutes, then transfer to a wire rack.