For the roaster, wash, halve and stone the plums. Lightly caramelise 100 g of sugar in a pot, add the plums and cinnamon, deglaze with wine and boil down for 5 minutes in a compote. Remove from the heat and set aside.
Preheat oven (electric cooker: 180 °C/circulating air: 160 °C/gas: see manufacturer). For the scouring, separate the eggs, beat the egg white with 1 pinch of salt until stiff. Cream egg yolk in a bowl with 100 g sugar. Stir in first quark, then flour, and finally fold in the beaten egg white.
Foam 2 tablespoons of butter in an ovenproof pan and fry the mixture for 2-3 minutes. Then cook for 10 minutes in the oven on the middle shelf. Remove from the oven and tear into pieces with two forks. Dust with icing sugar, add the rest of the butter and caramelise the slices over medium heat. Serve with roaster.