In a separate bowl, beat the egg whites with the cream of tartar using a hand mixer or stand mixer fitted with the whisk attachment until frothy. Add the remaining sugar gradually, a tablespoon at a time, while beating until stiff peaks form.

Add 1/3 of the egg whites to the batter, whisking until incorporated. We aren't worried about deflating the batter too much at this point.

Add another 1/3 of the egg whites and stir in with a spatula, taking care not to deflate the egg whites too much at this point. Transfer this mixture to the bowl with the remaining egg whites and fold just until combined.

Heat a non-stick skillet over low heat. Very lightly grease the pan with a little oil or non-stick cooking spray, then add three small scoops of batter to make 3 pancakes. Each scoop should only be about 2 tablespoons since you will continue adding batter to each pancake. Spoon another 2 tablespoons of batter directly on top of each pancake, then add a couple tablespoons of water to the pan around the pancakes and immediately cover with the lid. Cook for 2-3 minutes, then lift the lid and add a 3rd scoop of batter to each pancake mound and put the lid back in place. Cook 1-2 minutes more.

Once the pancakes have cooked for 5-6 minutes on the first side, add a 4th spoonful of batter onto the top of each pancake. You will ultimately use about 1/2 cup of batter total for each pancake. Carefully flip each pancake, then add another 1-2 tablespoons of water around the pancakes and cover with the lid again. Cook another 5 minutes or so until the pancakes are browned on both sides and cooked through.

Stack 3 pancakes on a plate and dust with powdered sugar. Top or serve with freshly whipped cream, fresh fruit, and maple syrup.