Set oven to 350F.
In a bowl, mix together all of the dry ingredients with a fork.
Prepare the flaxseed by mixing it with water and allowing it to thicken – about two to three minutes.
Slowly add the wet ingredients to the dry ingredients and stir with a spatula. Note: If the batter is too thick, feel free to add a few tablespoons of almond milk until it is to your desired consistency. If you prefer less dense muffins, then you may need to add some almond milk to the recipe.
Gently fold in blueberries and walnuts to the batter, careful not to mash them.
Spray the muffin molds with a little nonstick cooking spray and then evenly divide the batter among the muffin molds. If desired, lightly sprinkle a little coconut sugar on top.
Bake in the oven for 25 to 30 minutes until the muffins are golden brown, or until you can pierce it with a toothpick and it come out clean.