Halve, de-seed, and peel the avocados and place them into a food processor. Pulse until smooth.
Sift together the coconut flour, almond flour, and cacao powder. Add the erythritol, cinnamon, baking soda, and cream of tartar. Mix well.
Add the liquid stevia, eggs, coconut milk, and pureed avocado and process until well combined.
Roughly chop the chocolate and add to the mixture. Reserve a few pieces for topic.
Scoop the muffin batter into a silicone muffin pan or a regular muffin pan lined with paper cups greased with a small amount of coconut oil or ghee.
Top with the reserved chocolate pieces and place in the oven. Bake for about 25 minutes or until the tops are crispy and the muffins are firm.
Remove from the oven and let the muffins cool on a rack before serving. Keep at room termerature covered with a kitchen towel for up to three days or place in an airtight container and refrigerate for longer.
Shared with permission from The KetoDiet Cookbook. The recipe states that it yields 8 muffins, but I ended up getting 10.A one-for-one sugar substitute can be used in place of the erythritol and stevia. You'll need about 9 tablespoons of granular sweetener but the sweetness can be adjusted to taste.Although an electric mixer would probably work, a food processor is recommended to get the avocado nice and smooth. I also used the food processor to pulse in the dry ingredients.Add the chopped chocolate right into the food processor and stir it into the batter. There's no need for use a separate bowl.Instead of the baking soda and cream of tartar, you can try using a tablespoon of baking powder instead.