Whisk egg whites until frothy and set aside.

In a bowl, whisk together flour, baking soda, baking powder, salt, sugar, brown sugar and cinnamon. Add in egg yolks and streak in milk and vinegar until a smooth batter has formed.

Fold in egg whites.

Heat an ebelskiver pan to medium heat, and brush with melted butter. Sprinkle with ½ teaspoon of sugar, and scoop 2 tablespoons of the batter into each hole. Cook for 1–2 minutes until batter starts to pull away from the sides.

Using toothpicks or thin chopsticks, gently flip each pancake, and continue to cook for another 1–2 minutes until golden.
If cooking one of the variations, add half the amount of batter followed by mix-in ingredient(s), and seal with remaining batter, making sure to cover the mix-in.

To make the banana cream filling, mash banana and brown sugar in a bowl until smooth. Mash in cream cheese, mixing until smooth. Stir in vanilla pudding and maple syrup. Place mixture in a piping bag and refrigerate until ready for use.

I did not do this last step I just added the mashed bananas and chocolate chips and chopped walnuts so its optional if u wanna do it like that