Sheryl Julian, the award-winning food columnist for The Boston Globe, devised this recipe to use smoked mackerel, one of the most inexpensive fish on the market. You can substitute any smoked fish, such as whitefish, salmon, chub, or mullet. Serve with crackers.
Combine the fish, cream cheese, horseradish, mustard, and a pinch of cayenne pepper in a food processor. Taste and add salt and pepper, if you wish.
Let the flavors meld for several hours to one day before serving.