In a mixing bowl, whisk together 2 cups almond flour, 1/3 cup tapioca flour, 1/2 teaspoon cinnamon, and 1/2 teaspoon salt. Add 1 egg, 1/3 cup room-temperature butter, 3 tablespoons cane sugar, and 1 teaspoon vanilla extract (optional). Stir until soft and cookie dough-like.