Defrosting lobsters. Wash the potatoes and cook for about 20 minutes. Peel and press through. Stir in 50 g butter, then egg and egg yolk. Season. Pour into a piping bag. Peel and chop onion. Heat up with milk and bay leaf, let stand for about 10 minutes
Sweat flour in 25 g butter. Sieve the milk, add cream and bring to the boil. Season with salt, lemon, mustard and nutmeg. Separate scissors from lobster. Cut the lobster in half: place the knife at the head and divide it backwards
Cutting off heads. Remove the lobster meat from the shells and scissors and cut into pieces. Rinse lobster shells, pat dry and fill with 1-2 tablespoons of sauce each. Pour potato mixture as a thick rim into a greased, fireproof mould (approx. 28 cm Ø)
Place bowls in the middle of the mould. Fill in lobster meat. Spread the rest of the sauce on top. Sprinkle potatoes with cheese. Bake in a hot oven (electric cooker: 200 °C/circulating air: 175 °C/gas: level 3) for about 15 minutes. If necessary, gratinate under the grill for another 3 minutes