Sauce Velouté

Melt the butter in a heavy saucepan over medium-low heat until it foams but does not brown. Whisk in the flour all at once. Cook, stirring constantly, a touch longer than you would for a white roux — about 4 to 6 minutes — until the raw-flour smell gives way to a faint scent of toasted hazelnut and the paste takes on a pale straw color.

Off the heat, pour in the warm white stock in a steady stream, whisking constantly. Add it in three or four additions, letting each disappear before the next. Return to medium heat and bring to a gentle boil, whisking, until the sauce thickens and turns glossy. Lumps mean the stock went in too fast — whisk hard or strain.

Slide the pan half off the burner so the sauce simmers on one side only — this pushes a skin of fat, foam, and impurities to the cooler side (dépouillage). Simmer gently for 20 to 30 minutes, skimming the surface with a ladle every few minutes, until the sauce is glass-clear in color and reduced to a true nappe.

Season with fine sea salt and a small pinch of white pepper — white, so no dark specks mar the pale sauce. Taste and adjust. The velouté should taste of clean, concentrated stock, rounded and gently savory, never floury or flat.