BLACK TRUFFLE BUTTER:1 whole black truffle
8 oz (250 grams) butter, at room temperature
1 tsp (5 mL) freshly squeezed lemon juice
sea salt and white pepper to taste
1 Tbsp (15 mL) olive oil
1 cup (250 mL) chanterelles, cleaned and coarsely chopped
1 tsp (5 mL) minced garlic
1 cup (250 mL) chicken stock
3/4 lb (375 grams) Sablefish fillet, skin on, cut into four 3 oz/90 grams pieces
2 Tbsp (30 mL) olive oil
8 asparagus spears, peeled and blanched
1/3 cup (75 mL) pearl onions, peeled and blanched
Preheat oven to 375°F/150°
Shave half of the truffle into thin slices then cut into a fine dice. In a small mixing bowl, combine truffles with butter and mix well. Season to taste with lemon juice, salt and white pepper and set aside.
In a small saucepan over medium high heat, heat olive oil and add chanterelles and garlic and sauté until softened. Season to taste. Transfer mixture to a heatproof casserole dish; add chicken stock and bring to a boil. Turn heat to low, cover and simmer for 2 to 3 minutes. Remove from heat and set aside.
Season each side of Sablefish with salt & pepper. Heat oil in a skillet over high heat. Add Sablefish fillets, skin side down, and sear until skin is crisp, about 1 minute. Transfer fish to mixture in casserole dish. Place casserole into preheated oven and bake for 4 to 5 minutes. Remove casserole from oven, uncover and place over low heat. adjust seasoning of broth with salt and pepper. Add 2 Tbsp/30 mL of truffle butter and let it emulsify into the liquid.
Add warmed asparagus and onions to casserole. Take the remaining truffle and shave over Sablefish. At the table, divide contents of casserole onto four warmed plates and serve immediately.