1. For the mousseline, peel potatoes and simmer in salted water to cover until tender, about 15 minutes.

2. Drain the potatoes and run through a food mill. Pass potatoes through a fine sieve into a bowl. Lightly fold in the butter and cream, salt and black pepper corn. Set aside.

3. To prepare the sauce, boil wine and shallots in a 2- to 3-quart heavy saucepan over moderate heat until liquid is syrupy and reduced to 2 to 3 tablespoons, about 5 minutes. Add cream, salt, and white pepper and boil 1 minute.

4. Reduce heat to moderately low and add a few tablespoons of butter, whisking constantly. Add remaining butter, a few pieces at a time, whisking constantly and adding new pieces before previous ones have completely liquefied. Remove from heat, then season to taste with salt and pepper.

5. Rinse clams individually in cold water to remove all the sand. Drain.

6. Put oil and garlic in a large casserole. When hot, add the clams and ½ cup of wine. Cover tightly and cook for about 5 minutes, shaking skillet to redistribute the clams. When the clams have started to open, take out the clams from the shell.

7. Grill fish for 7 minutes, then turn and drizzle with butter. Continue cooking for 7 minutes, or until easily flaked with a fork.

8. Dress the mousseline potato in the hot plate, add the clams, grilled fish and finish with butter and
sea herbs for garnish.