four 6-ounce mackerel or bluefish fillets with skin
Directions
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.
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.
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.)
