Éperlans au Gratin

Éperlans au Gratin (smelts baked under a gratin crust) teaches one exact lesson: the fish and the crust must finish in the same moment. Smelts are so small that a moderate oven gives the sauce time to reduce only by turning the fish dry. Fierce heat is not bravado here, it is the timing mechanism.

The professional kitchen assumed a saucier on staff, a stock never off the fire beneath the prepared gratin sauce, brigade-sized dishes, and a range with a salamander ready to correct the surface. At home, begin with the finished, cross-referenced sauce, use one shallow metal dish, and preheat a heavy sheet pan in a 500°F oven. The broiler stands ready only for the last few seconds. Maintaining separate finishing stations is brigade scaffolding and can go; bringing a properly made sauce and truly fierce heat cannot. One cook, one stove, one evening.

For four people, sixteen smelts fit in one close layer. The whiting preparation gives two cooked mushroom caps to each fillet; this version keeps two per serving, because two on every little smelt would bury the fish and slow the crust. That is the single proportional change, made to preserve the balance rather than decorate it. Fully preheat the oven before assembling. That is the step that decides the dish.