Turbot with Cream Au Gratin
- 3 slices turbot , of about 11 oz each
- 1 lb duchess potato mixture
- 1 ½ cups Mornay sauce
- 1 ½ oz butter
- 1 egg
- 1 oz grated Parmigiano Reggiano cheese
- 1 lemon
Put the well-cleaned Turbot fillets (with their skin) into a casserole, cover with cold water, add 1 Tbsp of salt and 5 spoonfuls of milk for every liter (4 cups) of water and some slices of lemon peeled and seeded. Bring to the boil. As soon as the first bubbles appear, lower the heat and gently simmer for 20 minutes. At the same time, prepare the duchess potatoes and the Mornay sauce.
Remove the fish as soon as it is cooked, peel it and slice it. Butter an oven-dish and line it with the potato mixture, with an edge that is at least 1,5 inches high. Brush with beaten egg and add some spoonfuls of Mornay sauce.
Arrange on top the Turbot fillets still hot (if they have cooled down, they should be reheated). Cover with the rest of the Mornay sauce and sprinkle with grated Parmesan. Put the oven-dish into the oven. Serve when both the fish and duchess potato mix are nicely golden.