Preheat oven to 350F (180°C) and line a cookie tray with baking paper.
Add the almond flour, baking powder, and salt to a medium mixing bowl and whisk until well-combined and there are no lumps of flour.
Make a “flax egg” by mixing the 1 tbsp. flax powder and 3 tbsp. water together in a small bowl. Allow to sit for 5 minutes. Alternatively, could use 1 egg if not vegan.
Add the flax egg, pumpkin puree, melted coconut oil, and vanilla extract to a bowl and whisk together until smooth.
Add the brown granulated erythritol to the wet ingredients. Stir until well-combined and most of the sweetener granules are dissolved.
Add the wet ingredients to the almond flour mixture. Stir until the dough sticks together well and has a similar texture to regular cookie dough. If the dough is too wet, add another 1/4 – 1/2 cup of almond flour.
Oil your hands, then roll 2 tbsp. of dough at a time into a ball and place on the baking sheet. You should end up with 12 cookie dough balls. Use a fork to press each ball down crosswise until they’re about 1/2 inch (1 1/2 cm.) thick.
Bake for 15 – 20 minutes at 350F (180°C) until just starting to brown and turn golden. Remove from the oven and sprinkle with brown erythritol and cinnamon while warm.
Allow the cookies to cool on the cookie tray for 20 minutes. Then, carefully transfer them to a wire cooling rack to finish cooling.