Clean and wash broccoli and cut into florets. Clean and wash the sugar snap peas. Boil up about 3/8 litres of water, stir in broth. Cover the broccoli and cook for about 6 minutes. Add mangetout and peas and cook for 1-2 minutes. Pour off, catch the broth.
Pour the vegetables into an ovenproof dish. Peel onion and chop finely. Fry in hot fat. Sprinkle with flour and sweat. Stir in about 3/8 litres of water, cream and stock. Bring to the boil and simmer for about 5 minutes. Season to taste. Mix egg yolk and some sauce, then stir into the rest of the sauce (do not boil any more!). Wash the salmon, dab dry and cut into 4 pieces. Sprinkle with lemon juice and season with salt. Put it on the vegetables and pour the sauce over it. Bake in the preheated oven (electric cooker: 200 °C/ convection oven: 175 °C/ gas: level 3) for about 20 minutes.
Season to taste. Mix egg yolk and some sauce, then stir into the rest of the sauce (do not boil any more!). Wash the salmon, dab dry and cut into 4 pieces. Sprinkle with lemon juice and season with salt. Put it on the vegetables and pour the sauce over it. Bake in the preheated oven (electric cooker: 200 °C/ convection oven: 175 °C/ gas: level 3) for about 20 minutes. Sprinkle the gratinated salmon with lemon julienne and garnish with lemon wedges and tarragon. Serve with ribbon noodles