Preheat the oven to 375
Blend all of the wet ingredients (bananas, milk, maple syrup, 3 TBSPs oil, applesauce, apple cider vinegar, and vanilla extract) in a food processor, blender, or with a hand whisk.
Sift the flour, salt, baking powder and spices into a bowl. Stir in the oats, coconut, and any other add ins in a larger bowl and mix well.
Add the wet mixture into the dry ingredient bowl slowly and mix well into a batter. Don't over mix- keep a delicate hand. You're done as soon as the mixture comes together!
Pour batter into a lightly oiled muffin pan ¾ of the way up each cup. If you use liners make sure they are quality as they can stick to the sides of the muffins and tear when removing. I find it helpful to spray with non-stick spray, but no liner works great too.
Make the streusel by mixing the flour, sugar, cinnamon, and oil into a crumble.
Place the crumble streusel on top of the batter of each muffin.
Place the muffins in the oven and bake for 25 minutes (check with toothpick or knife so they come out clean)
Place on a rack to cool! Cool to room temperature and enjoy!