Grease a springform pan (26 cm Ø; approx. 8 cm high) and sprinkle with breadcrumbs. Mix quark, eggs, sugar, pudding powder, lemon peel and lemon juice until smooth. Spread into the mould. Bake in the preheated oven (electric cooker: 175 °C/circulating air: 150 °C/gas: level 2) for 50-60 minutes (if necessary, cover shortly before the end of the baking time).
Take the cake out of the oven and remove it from the edge of the mould with a knife. Cool in the mould on a cake rack for about 1 hour, then remove from the mould and let it cool completely.
Whip the cream until stiff, adding vanillin sugar and cream firming agent. Spread loosely on the cake. Serve with red fruit jelly.