Preheat oven to 350°. Line muffin cups with parchment paper cups.
Melt the coconut oil in a small saucepan and set aside.
In a large mixing bowl, add the dry ingredients. Cassava flour, arrowroot flour, collagen, coconut sugar, baking soda, cream of tartar, sea salt, and cinnamon. Whisk until well combined.
Mix in the eggs, coconut oil, applesauce, and vanilla with the dry ingredients. Once blended fold in the blueberries. (You can chop the whole cup or chop half and toss in half whole.)
Add a 1/3 c of batter to the muffin cups.
In a food processor add the crumble topping ingredients; finely shredded coconut, coconut sugar, gelatin, and either cold coconut oil OR cold butter. Pulse until crumbles. Sprinkle over the 12 cups.
Bake at 350° for 25-30 minutes. When a toothpick comes out clean they are done. Let them in cool for 10 minutes and then move the muffins to a cooling rack.