Pate aux Pommes de Terre

Pate aux pommes de terre is a savory potato pie whose origins are contested among Berry (Centre-Val de Loire), Limousin (Haute-Vienne and Creuse), Bourbonnais (Allier), and the northwest of Auvergne. Wikipedia documents it across all these regions; the oldest versions used a bread dough baked in a clay tourtiere, and the modern version most often uses puff pastry. The pie consists of sliced potatoes layered with creme fraiche and aromatics — onion, garlic, parsley — between two crusts; some Limousin versions add garlic sausage or meat. It is a peasant dish of the central French countryside, built on cheap starch and the dairy of the region.

A wedge of pate aux pommes de terre brings up a flaky golden crust, sliced through to reveal layered potatoes bound in a glossy, creamy sauce of creme fraiche and softened onions. The potato is tender and yielding, having cooked in the dairy's steam within the sealed crust; the flavor is buttery, gently garlicky, and earthy. Eaten hot, often with a green salad.

Pate aux pommes de terre rests on steam-baking in a sealed double crust. The thinly sliced raw potatoes are layered with creme fraiche and aromatics between two sheets of pastry; the pastry seals the interior from the oven's dry heat, so that the potatoes cook in the steam of their own moisture and the dairy's. The creme fraiche — high in fat and with a lactic acidity — both lubricates and gently tenderizes the potatoes, while its fat prevents the starch from turning sticky. The long, moderate bake gelatinizes the potato starches and cooks them through without drying them out; the crust, exposed to the dry oven heat, browns and crisps by Maillard reaction. The sealed interior is the key — it is essentially a pressure-cooked pie.