1 Piece sushi grade tuna loin (about 1 pound -- cleaned) 2 Tablespoons black sesame seeds 2 Tablespoons white sesame seeds 2 Tablespoons chopped shallots 1 Sprig fresh thyme 1/2 Tablespoon cracked black pepper 1 bay leaf 1/2 Cup white wine 1/4 Cup heavy cream 1 Stick butter (cut into small pieces -- at room temperature) 1 Tablespoon wasabi paste -- diluted with 1/2 tablespoon rice vinegar Season tuna with salt and pepper on each side. Combine black and white sesame seeds and roll tuna in mixture. Set aside. In a saucepan simmer shallots, thyme, pepper, bay leaf and white wine. Reduce slowly until dry. Add heavy cream and bring to a boil. Slowly whisk in butter, one piece at a time. Season with salt and pepper, strain, and keep beurre blanc warm. In a large skillet sear tuna, lightly brushed with olive oil, for 2 minutes on each side. Slice into 12 medallions. Serve immediately on serving plates. Drizzle with beurre blanc and wasabi mixed with the rice vinegar.
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