Oven-baked fish in cream sauce

This is a nice fish dish that my mother sometimes makes. I make no claims about its traditionality.Serves 2:400 g fish fillets (mom uses cod or haddock, but try plaice, sole, flounder or other white fish)1/2 tsp salt25 g butter or margarine50 ml cream100 ml milk1 tbs breadcrumbs (Paxo crumbs look nice and colourful, but home-made ones are fine)2 tbs grated cheese (mom uses Gouda, but I imagine