Preheat the oven together with the tray to 225 ° C.
Mix the flour with the milk until smooth, stir in 1 pinch of salt, 1 tablespoon of sugar and the 3 egg yolks. Beat the 3 egg whites with a pinch of salt and 1 tablespoon of sugar until very stiff. Take the hot tray out of the oven, grease, pour the dough on it and smooth it out. Spread the plums on the dough. Place the egg whites on the dough with a tablespoon and sprinkle with the cinnamon sugar. Put the pancake in the middle of the oven and bake for about 12-15 minutes.
Roll up the hot pancake, cut into slices and serve with vanilla ice cream.