Preparation / Directions:
Heat butter in frying pan until foaming subsides, reduce heat to medium to medium low and fry fish five minutes per side, being careful when you turn it not to break it up.
While fish is frying, combine sauce ingredients.
When fish is done, remove to plates or serving platter. Deglaze pan with the sauce, stirring briskly until it begins to thicken just slightly. Pour sauce decorously over the fish, and serve.
Other mild, tasty vinegars could be substituted. If all you have is wine or cider vinegars, use two Tbs of that and two Tbs of some kind of unsweetened fruit pulp or juice.
Since you don't have Muscatine wine, substitute a dry gewürztraminer or maybe a Riesling- anything dry, with a spicy or fruity flavor.
Other thick, firm fish ought to do. Fry it five minutes per side per inch of thickness