Sauce Matelote — Red Wine Fish Stew Sauce

Ingredients

• 1.2 kg freshwater fish (eel, pike, carp, or perch, or a combination), eel skinned and cut into 5 cm tronçons; other fish cut into serving pieces
• 60 ml Cognac, for flambéing
• 750 ml red wine, Burgundy or Alsatian Pinot Noir, full-bodied; not overly tannic
• 2 onions, peeled and roughly chopped
• 1 bouquet garni, thyme, bay, parsley stems
• 60 g mushroom trimmings
• For the beurre manié
• 30 g unsalted butter, softened
• 30 g plain flour
• For the garniture matelote
• 200 g pearl onions, peeled
• 20 g unsalted butter, for glazing the onions
• 1 tsp caster sugar
• 50 ml red wine, splash for glazing the onions
• 200 g button mushrooms, wiped clean, left whole or halved if large
• 30 g unsalted butter, for sautéing the mushrooms
• 150 g lardons of bacon, blanched
• 4 heart-shaped croûtons of bread, fried in clarified butter until golden
• 60 g clarified butter, for frying the croûtons

Method

1. 1
   Prepare all garniture elements in advance so they are ready to serve. Glacé the pearl onions: place in a small sauté pan with the butter, sugar, and a splash of red wine. Cook over moderate heat, turning occasionally, until the liquid is absorbed and the onions are tender, browned, and gleaming with glaze. Reserve. Sauté the button mushrooms in butter over high heat until coloured and cooked through. Blanch the lardons in cold water brought to the boil, drain, and colour lightly in a dry pan. Fry the heart-shaped croûtons in clarified butter until deep gold on both sides. Reserve all garnishes separately. The onions are done when they gleam and yield without resistance to the point of a knife.
2. 2
   Work the softened butter and flour together with a palette knife or fingertips until completely homogeneous and no dry flour remains — this is the beurre manié. Divide into small, pea-sized pieces and reserve at room temperature.
3. 3
   Season the fish pieces. Heat a wide, heavy braising pan over high heat. Add a film of oil or butter. When hot, lay in the fish pieces and colour briefly on both sides. Pour over the Cognac and flambé, shaking the pan until the flames subside. The surface of the fish should show caramelised colour and the sharp smell of raw spirit must be gone.
4. 4
   Add the chopped onions, mushroom trimmings, and bouquet garni to the pan. Pour over the red wine — the liquid should just cover the fish. Bring to a simmer and cook gently until the fish pieces are just cooked through and yield to gentle pressure. Remove the fish carefully and reserve covered. Strain the braising liquid and discard the solids.
5. 5
   Return the strained braising liquid to a wide saucepan and reduce over vigorous heat by two-thirds. This is where the dish lives or dies: insufficient reduction produces a thin, watery sauce without the intensity that defines matelote — the liquid must become deep burgundy, noticeably concentrated in aroma, and syrupy at its edges.
6. 6
   Reduce the heat to a steady simmer. Begin adding the beurre manié piece by piece, whisking constantly and allowing each addition to dissolve fully before adding the next. Never add more than one piece at a time. Continue until the sauce reaches a velvety, glossy consistency that coats the back of a spoon and holds a clear line when a finger is drawn through it.
7. 7
   Return the reserved fish gently to the sauce to warm through without further cooking. Taste and adjust seasoning. The flavour should be that of concentrated red wine, fish, and the subtle sweetness of the glazed onions, all bound in a glossy, butter-enriched body.
8. 8
   Transfer the fish and sauce to a serving dish or deep plates. Arrange the garniture matelote — glazed pearl onions, sautéed mushrooms, blanched and coloured lardons — over and around the fish. Place the heart-shaped croûtons at the edges. The finished dish should be deep burgundy, glossy, and the garnish elements distinct and unmuddled.