Tarte aux Quetsches

The Tarte aux Quetsches is autumn’s defining tart in Alsace and Lorraine, built upon the Quetsche d’Alsace (Prunus domestica subsp. insititia)—a small, oval, blue-violet plum with deep amber flesh that ripens in September. Unlike the mirabelle, the quetsche has a firmer, more acidic flesh with lower sugar content (around 18-20°Brix), making it ideal for baking where its tartness provides counterpoint to sweet pastry and custard. The authentic preparation uses pâte brisée rolled to 3mm, fitted into a buttered tart ring, and blind-baked briefly at 190°C for 10 minutes. The quetsches are halved, pitted, and arranged standing upright in tight concentric circles—the density of the arrangement is critical, as the plums shrink by roughly 30% during baking and gaps become unsightly holes. A sprinkle of cinnamon sugar (2:1 sugar to cinnamon) goes over the fruit before baking at 180°C for 30-35 minutes. The tart is done when the plum edges are deeply caramelised and the juices have concentrated into a syrupy glaze between the fruits. Some bakers add a thin layer of ground almond or semolina on the blind-baked base to absorb excess juice—a professional trick that prevents the dreaded soggy bottom while adding subtle texture. The tart is best served barely warm, when the concentrated plum flavour is at its most aromatic, with a dollop of crème fraîche or a scoop of cinnamon ice cream.