German Cheesecake (Käsekuchen) vs Flan Casero (Homemade Spanish Caramel Custard)

Both desserts lean on milk, sugar, eggs, an extra yolk and vanilla, but put them to very different work. The Käsekuchen beats eggs into lemon-scented quark, binds it with a cornstarch-and-milk slurry and melted butter, and bakes it over a buttery, lemon-zested shortcrust, giving a chilled, set filling on a contrasting base. The flan instead warms whole and condensed milk, tempers it into gently whisked eggs, strains it and bakes it in a water bath over deep amber caramel, yielding a silky custard that is inverted so the caramel cascades over it.