Preheat oven to 350F, and spray the mini muffin tin with some nonstick cooking spray.
In a bowl, whisk together the egg, egg whites, and brown sugar. A hand mixer or Kitchenaid is best in order to whip air into the egg whites. Add in the apple sauce, vanilla, and milk.
In a separate bowl, mix together the flour, cinnamon, baking powder, baking soda, and apples. Coating the apples in the flour will help them not fall to the bottom of the muffins. Fold the dry ingredients into the wet gently.
Pour batter into mini muffin tin evenly.
In a small bowl, mix the 2.5T of all purpose flour with the white sugar and add in the melted margarine. Mix with a fork until tiny crumbs form- it will take a few minutes of mixing.
Divide the crumb topping over the 36 muffins, then put the caramel sauce into a small zip-lock bag. Cut a tiny hole in the tip of the bag - make sure it's very tiny or the sauce will not cover all 36 muffins. Drizzle a small amount over each muffin. This will give them an extra pop of sweetness!
Bake in the oven for approx 18 minutes.