- 8 pickled cocktail onions, finely chopped
- 1/4 cup finely chopped mixed sweet pickles or dill pickle
- 4 teaspoons country-style Dijon mustard
- 1/2 stick (1/4 cup) unsalted butter, softened
- 1/2 teaspoon salt
- 1/4 teaspoon black pepper
- 6 (4- to 6-oz) pieces mackerel fillet with skin
- Accompaniment: lemon wedges
- Preheat broiler. Oil a large shallow baking pan.
- Stir together onions, pickles, mustard, butter, 1/4 teaspoon salt, and 3/4 teaspoon pepper in a small bowl.
- Arrange fish, skin sides down, in baking pan and sprinkle with remaining 1/4 teaspoon salt and 3/4 teaspoon pepper. Spread butter mixture on fish and broil 5 to 6 inches from heat until fish is just cooked through, 4 to 6 minutes.