Ingredients

3 medium tomatoes (1 pound)

　　1 small onion

　　1/3 cup apple jelly

　　3 tablespoons cider vinegar

　　2 tablespoons chopped fresh tarragon leaves

　　1/2 teaspoon dried hot red pepper flakes

　　1/4 teaspoon salt

　　four 6-ounce mackerel or bluefish fillets with skin

　　

Step 1

Have ready a bowl of ice and cold water. Cut an X in blossom end of each tomato and in a saucepan of boiling water blanch 10 seconds. With a slotted spoon transfer tomatoes to ice water to stop cooking. Peel tomatoes and seed and chop. Chop onion.

　　

Step 2

In a 1-quart saucepan bring tomatoes, onion, jelly, vinegar, tarragon, red pepper flakes, and salt to a boil over moderately low heat and cook, stirring frequently, until thick, 30 to 40 minutes. Cool jam to room temperature. Jam keeps, covered and chilled, 1 month. Bring jam to room temperature before serving.

　　

Step 3

Prepare grill. Season mackerel fillets with salt and pepper and grill, skin sides down, on a lightly oiled rack set 5 to 6 inches over glowing coals until just cooked through, 9 to 13 minutes. (Do not turn fish.)

　　

Step 4

Serve each fillet topped with 2 tablespoons jam.