Gather the ingredients. Heat the oven to 350 F/176 C.
Line a 12-cup muffin tin with paper muffin liners.
For best results, use a kitchen scale to weigh the ground flax meal and almond flour and then place in a large mixing bowl.
Whisk in the gluten-free baking powder, ground nutmeg, cinnamon, and salt.
Add the melted butter, eggs, sugar, and water or buttermilk to the dry ingredients and stir to combine; alternatively, you can use an electric mixer and beat just until the ingredients are blended.
Use a small ice cream scoop or large spoon to distribute the muffin batter evenly (about ⅔ full) into the prepared muffin tin.
If you are using the toppings, mix together the cane sugar, nutmeg, and cinnamon in a small bowl.
Sprinkle about 1 teaspoon of the sugar-spice mixture on top of each muffin.
Bake in the oven for about 20 minutes or until a toothpick inserted into the center of a muffin comes out clean.
Allow the muffins to completely cool before serving.
Enjoy as a sweet treat, breakfast, or as a quick grab-and-go snack.
