Making a sauce for fish

I wanted to add this to my original question but I figured no one would see it.
Iam preparing a roulade of salmon( stuffed with spinach, leeks, shrimp,shallots, onions and garlic) which Iam poaching in a flavorful courtbouillon that will have mirepoix white wine etc in it.
I need to make a Veloute' sauce.
I would like to incorporate the court bouillon with the Veloute' and some fish fume'to make the sauce
What would be the proper quantities of each liquid to make a sauce for the salmon?
Thank you
Danielle

[chefjohnpaul]

That would depend on how strong your court-bouillon is. If you've poached the salmon in it your sauce may have an overwhelming salmon edge as salmon is an oily fish. Why not make a veloute' out of the fume', a little white wine, then finish with cream and a little butter. It will complement the salmon without being 'salmony'.

I would say a little buerre blanc made with shallots, white wine, white wine vinegar, fume', and whole butter may even be more delicate. To me buerre blanc is the ultimate seafood sauce.