Preheat the oven to 325F and grease a mini muffin tin (24 cavity) very well. (I double grease, first with butter and then with coconut oil spray).
In a blender combine the eggs, sweetener and vanilla extract. Blend until smooth.
Add the coconut flour, melted butter, baking powder, salt, and cinnamon. Blend again until smooth. Let the batter rest a few minutes to thicken.
Add 1/3 cup of the water and blend again. If it's still very thick, add a little additional water. You shouldn't be able to pour it, but you should be able to scoop it out of the blender easily.
Divide among the prepared muffin cups. Add a few blueberries to each (I found 4 to 5 to be just about right). Press them gently into the batter.
Bake 20 to 25 minutes, until set. Let cool a few minutes in the pan and then serve with your favourite low carb pancake syrup.