Mix the fat with sugar, vanilla sugar and egg yolk until frothy, then stir in lemon juice and zest, salt, quark and semolina or starch. Then fold in the egg white, which has been beaten into snow.
Pour half of the quark mixture into a greased baking dish and cover with 2/3 of the drained apricots. Then pour the rest of the quark mixture over it. Decorate with the remaining apricots and flaked almonds and cover with flakes of butter.