A fairly cheap and very easy main dish, which I made this way because I get so tired of the same old methods and ingredients. Instead of breadcrumbs I used butternut, which goes well with all fish. The butternut can be substituted with the same amount of sweet potato. Remember you don't have to peel butternut -- what a job that is! Slice in two and bake in the oven, the peel becomes soft, and the flesh can be scooped out. I used pre-prepared butternut chunks. Do adjust seasonings to taste, but it really does need a tangy mayonnaise. The ingredients are in almost all pantry cupboards! Cooking time includes roasting the butternut.