Separate the eggs. Using a hand or stand mixer with a whisk attachment, whisk the egg whites with a pinch of salt until stiff peaks form. Set aside.
3 eggs
In a large mixing bowl, combine flour and milk and whisk until you can no longer see any lumps. Add in the egg yolks, carbonated / seltzer water, sugar, and salt, and mix to a thick dough.
225 g flour, 180 ml milk, 60 ml carbonated water /seltzer water, 1 pinch salt, 1 pinch sugar
Carefully fold in the egg whites, and leave the mixture to rest in the fridge for approximately 30 minutes. This will allow the gluten in the batter to develop and give the pancake stability.
In the meantime core and slice apples into thin thin.wedges (0.5 cm). Pour over the lemon juice, so the apples do not brown and sprinkle with the brown sugar.
4 apples, 4 teaspoon brown sugar
Heat the butter or vegetable oil in a coated frying pan on medium-high heat. Once the butter is melted and starts sizzling use a ladle to add the dough to the pan. The dough is a little thick, so you might need to distribute it with a spoon.
4 tablespoon butter or vegetable oil
The last thing is to lay the apple slices in a circular pattern on top of the pancake batter. Cook on low to medium heat for approx 2-3 minutes. Exact cooking times may differ. You will notice that the pancake is ready by checking if you can lift the sides of the pancakes.
To prevent the pancake from breaking, place a serving plate over the pan. Pressing down on the plate firmly with your free hand while flipping the pan over using the other hand, so that the plate catches the pancake. Now place the pan down & slide the pancake back into the pan from off the plate. Cook on the other side for a further 2-3 minutes
To serve you sprinkle the pancake with cinnamon sugar.