Preheat oven to 160 ° C.
Reduce the white wine, pour water, add lemon slices and onion rings and season with the bay leaf and seasalt. Boil up, add the salmon fillets and poach for 10 minutes in the oven.
For the vegetables, boil potatoes, peel and slice them. Wash spring onions and cut into equal pieces.
Melt butter in a saucepan, toss potato wedges and spring onion pieces in it, then stir in creme fraiche and season with salt and pepper.
Remove salmon fillets, pour some of the fish stock into the vegetables and season to taste.