In a medium mixing bowl, whisk together the mashed bananas, egg, almond butter, sweetener and vanilla extract. You can also do this in a blender if preferred.
Stir in the almond flour, baking powder, salt, cinnamon, chia seeds and chocolate chips and mix well.
Line a muffin tin with baking cups and fill each one 3/4 of the way with the batter.
Top with a few extra chocolate chips before baking. For mini muffins, bake for 15-20 minutes, for regular sized muffins bake 20-25 minutes- until the tops are firm to touch.
Store in an airtight container on the counter for up to 3 days, or in the fridge for up to 1 week. I love to warm them in the oven or microwave before serving.