Preheat oven to 350°F/175°C. Line a traditional muffin pan with 12 liners.
In a large bowl, stir together the almond flour, erythritol, baking powder, and salt. If desired, remove a few teaspoons of the almond flour mixture and add it to the blueberries; toss to coat. Set aside. Coating the blueberries in the dry ingredients will help keep them from sinking in the muffins.
Add the melted butter, almond milk, eggs, and vanilla to the almond flour mixture. Stir until combined. Fold in the blueberries.
Portion batter evenly into the 12 prepared muffin liners. Bake for around 20 minutes, until the edges are golden brown and a toothpick inserted into the center comes out clean.
Air Fryer Instructions:
Fill 12 silicone muffin liners and bake for 10-12 minutes at 330˚F/165˚C or until internal temperature reads 180˚F/82.2°C.
Notes
Use fresh or frozen blueberries. Do not thaw the frozen blueberries though. For dairy-free version, use coconut oil in place of butter.