Remove the outer savoy cabbage leaves. Cut the savoy cabbage into slices, remove the stalk. Cut cabbage into strips and wash carefully. Blanch in boiling salted water for 2 minutes, drain well. Wash the salmon and cut into pieces so that the salmon are laid side by side to form a layer. If necessary, cut thick pieces of salmon a little flatter.
Peel and finely chop the onion. Melt butter and fry onion until transparent. Add flour and sauté while stirring. Add stock, milk and cream while stirring, bring to the boil briefly and simmer for 2-3 minutes. Season to taste with salt, pepper and lemon juice. Grease a high casserole dish (approx. 16 x 25 cm). Spread 2 tablespoons of sauce in it. Place 3 sheets of lasagne on top. Spread the sauce one after the other, spread half of the savoy cabbage, cover with 3 sheets of lasagne, spread with sauce. Spread the salmon, season with salt and pepper, spread 3 lasagne sheets, the remaining savoy cabbage, sauce and last noodles. Finish with sauce. Grate cheese and sprinkle on top.
Spread 2 tablespoons of sauce in it. Place 3 sheets of lasagne on top. Spread the sauce one after the other, spread half of the savoy cabbage, cover with 3 sheets of lasagne, spread with sauce. Spread the salmon, season with salt and pepper, spread 3 lasagne sheets, the remaining savoy cabbage, sauce and last noodles. Finish with sauce. Grate cheese and sprinkle on top. Bake in the preheated oven (electric cooker: 175 °C/ convection oven: 150 °C/ gas: level 2) for about 40 minutes. Serve garnished with chervil
With 8 people: