Heat your oven to 350F and line or grease a standard muffin tin. I really like silicon liners because they're reusable and come in fun colours.
First off, mix your flax egg. This is one tablespoon ground flax and three tablespoons of water. Combine and let it gel up while you prepare your other ingredients.
Mix the flour, baking soda, cinnamon, nutmeg, and frozen blueberries in a large bowl. Adding the blueberries to the dry ingredients helps to keep them from bleeding.
In a medium bowl, combine the almond milk, applesauce, maple syrup, coconut oil, vanilla, mashed bananas, and the flax egg.
Add wet ingredients to dry and stir just to combine. Fill the muffin tin about 3/4 of the way full for each cup and bake for 25-27 minutes, or until a toothpick comes out clean. I'm not sure if it's because it's crazy hot and humid here today, but this batch seemed to take a few minutes longer to bake than usual.
Remove and place on a cooling rack. I recommend storing these in the fridge or freezer, especially if your home is warm.