Prep the pan and oven: Preheat your oven to 350°F (175°C). Lightly grease a 6-cavity donut pan with butter or nonstick spray. If using a silicone pan, place it on a baking sheet for stability.

Mix dry ingredients: In a medium bowl, whisk together almond flour, coconut flour, sweetener, baking powder, cinnamon, and salt until no lumps remain.

Whisk wet ingredients: In a separate bowl, whisk eggs, yogurt, melted butter, and vanilla until smooth. The mixture should be creamy and uniform.

Combine and adjust: Stir the dry ingredients into the wet mixture. Add 2 tablespoons almond milk and fold until just combined. If the batter seems very thick, add another tablespoon of almond milk. It should be scoopable, not runny.

Fill the pan: Spoon the batter into the donut cavities, filling each about 3/4 full. For cleaner edges, pipe the batter using a zip-top bag with the corner snipped.

Bake: Bake for 14–17 minutes, or until the tops are set and a toothpick comes out clean. The donuts should spring back lightly when touched.

Cool completely: Let the donuts rest in the pan for 5 minutes, then transfer to a cooling rack. Cool fully before coating to avoid melting the sweetener too quickly.

Make the coating: In a shallow bowl, mix the erythritol and cinnamon. In a separate small bowl, have the melted butter ready.

Coat the donuts: Brush each donut lightly with melted butter, then dip and roll in the cinnamon “sugar” mixture until well coated. Tap off excess.

Serve: Enjoy right away or let the coating set for 10–15 minutes for a less tacky finish.