The point here is to brown the salmon, but not to cook all the way through, because once you cook the sauce, you will add the cooked salmon back to the pan and continue cooking. In this recipe I prepared my own vegetable stock, you may also use fish or chicken stock as well. I also used Half and Half (half cream, half milk), the sauce will look prettier if you use heavy cream. I did not have heavy cream, but I can assure you this tasted good.
1 cup vegetable stock
¼ cup white wine
2 TBSP lemon juice
1 TBSP butter
¼ cup heavy cream
(corn starch, if your sauce is too liquid: mix in a little cold water and add to the sauce, if necessary)
1 TBSP Dijon mustard
1 tsp mustard seeds, crush
1. brown salmon in olive oil, then remove from the pan.
2. add stock, white wine, lemon juice and reduce liquids to half, then add butter, dijon mustard and mustard seeds.
3. finally add cream, put salmon back into the pan.
4. sprinkle fresh parsley before serving.
Source: Classical Cooking from Philip Pauli