Zwiebelkuchen (German Onion Tart) vs Soufflé au Fromage: Classic French Cheese Soufflé

Both dishes lean on milk, butter, eggs and a pinch of nutmeg, yet put them to very different work. In the Zwiebelkuchen, milk and butter enrich a yeasted dough, while eggs bind a sour cream custard poured over slowly sautéed, sweet onions and crisp smoked bacon, with optional caraway adding an earthy note. The soufflé turns milk and butter into a Gruyère-enriched béchamel, then relies on stiffly whipped egg whites for its airy lift. One is hearty, tangy and savory; the other is light and cheesy, with a delicate, ephemeral richness that demands immediate service.