Preheat oven to 400° F / 204° C
Thoroughly grease a 6 cup muffin tin with coconut oil or line with paper muffin liners.
Melt coconut oil if it is not liquefied. Make sure the other ingredients are at room temperature. Mix the first five ingredients together. Add the coconut flour, almond or hazelnut flour, baking powder, and whisk together until smooth.
Bake at 400° F / 204° C for 15 minutes (see note) or until a toothpick inserted in a muffin comes out clean. Pop muffins onto a wire rack to cool, then store in a container and refrigerate. Flavor is best one or two days after baking.