Rognons de Veau Flambés — Veal Kidneys Flambéed in Cognac

Veal kidneys (rognons de veau) are the most prized of the French offal cuts — their firm, almost meaty texture and clean, mineral-sweet flavour make them suitable for the finest restaurants. Flambéed with Cognac and finished with mustard cream, they represent the rôtisseur's mastery of rapid, high-heat offal cookery. The kidney must be veal (rognon de veau), which has a pale rose colour and mild flavour — lamb kidneys are acceptable but stronger; beef and pork kidneys are too pungent for this preparation. Preparation: peel the transparent outer membrane, halve the kidney lengthwise, and remove the core of white fat and sinew (this fat has an unpleasant, urinous flavour if left in). Cut into 2cm thick slices or leave in halves for a more dramatic presentation. Season. Heat a heavy sauteuse until very hot, add clarified butter, and sear the kidney pieces for 2 minutes per side — the exterior should be mahogany brown while the interior remains distinctly pink (55-60°C; kidney cooked past 65°C becomes grey, rubbery, and releases an unpleasant liquid). Remove and rest on a warm plate. Deglaze the pan with 50ml Cognac, flambée until the flames die, add 2 minced shallots, cook 30 seconds. Add 100ml veal jus, reduce by half. Finish with 2 tablespoons double cream and 1 tablespoon Dijon mustard — the mustard goes in off the heat (boiling it produces bitterness). Return the kidneys to the sauce briefly to coat. Serve immediately in a cocotte or on a warm plate with the sauce pooled beneath.