Mix the flour, salt, milk, sugar and the egg into a loose batter. Peel the apple and cut into thin slices.
Melt the butter in a pan. Now pour the batter into the pan and spread the apple slices over it. When the dough is slowly loosening and the underside has turned a golden color, turn it carefully and lightly brown the other side as well.
Meanwhile, heat the calvados in a ladle (made of metal, of course) over a warmer. Take the pan off the stove, ignite the calvados and pour it over the pancake while it is burning.
To serve, divide the pancake and sprinkle with cinnamon sugar.
Vanilla ice cream and / or a homemade caramel sauce, refined with calvados, round off this simple yet sophisticated dessert.