Preheat oven to 200c/400f. 1 For the Lobster Stock: Remove the meat from the lobster shell and claw and reserve. 2 Place the empty shell and claws in a pan with the olive oil, wine, stock cube and tarragon sprig. Add 1/2 pint water, simmer for 10 minutes and strain. 3 Cut out four circles from the lasagne sheets with a plain cutter. Place in a pan of boiling water until cooked. Drain. 4 For the Filling: In a bowl mix the lobster meat with the basil. Season. Lay two pasta circles in an ovenproof dish and spoon on some filling. Top with another circle and place in the oven for five minutes to heat through. 5 For the Sauce: Heat the butter in a pan and add the watercress, pepper, cream and strained stock. 6 Cook for five minutes, then puree in a blender or mini food processor. Serve over the ravioli, reserving 2 tbsp for the Welsh rarebit. Per serving: 126 Calories (kcal); 14g Total Fat; (93% calories from fat); 1g Protein; 1g Carbohydrate; 0mg Cholesterol; 21mg Sodium Food Exchanges: 0 Grain(Starch); 0 Lean Meat; 0 Vegetable; 0 Fruit; 2 1/2 Fat; 0 Other Carbohydrates Converted by MM_Buster v2.0n.