Preheat your oven to 350 degrees Fahrenheit.
Place 8 unbleached muffin cup paper liners in a standard muffin tin. If you're not using muffin cups, grease 8 of the muffin tin cups with oil or butter. After you've measured out 2 cups of almond flour, scoop out 4 teaspoons and place it in a small cup or bowl. Set aside until you're ready to sprinkle it on the tops of the muffins just before baking
In a large bowl combine the remaining almond flour with the coconut flour, baking powder and salt.
In a separate bowl whisk together the eggs, honey and vanilla, then add the wet ingredients to the dry ingredients and mix thoroughly.
Gently fold in the blueberries with a large spoon or spatula.
Divide the blueberry muffin batter between nine cups. (You'll want to use approximately 1/3 cup batter per muffin cup.)
Pour the 2 teaspoons oil or melted butter into a small bowl and dip your fingers into it. With lightly oiled hands, pat down the tops of the muffins.
Sprinkle with the almond flour you set aside.
Place the muffin pan in the oven and bake for 20-25 minutes, or until the tops are springy yet lightly firm. They should feel just the tiniest bit undercooked in the center when pressed. That’s perfect - the muffins continue to cook a little while they’re resting in the pan after you remove them from the oven. Of you wait until a toothpick comes out completely clean they'll be overcooked.
Allow to cool in the pan for 5 minutes before serving warm or transferring to a wire rack to cool to room temperature.