Jamaican cooks make magic with fish. Dishes like run down aren't complicated, but they are definitely more than the sum of their parts. (The name originates from the way the fish is cooked until it falls apart, or "runs down.") When big chunks of fresh-caught fish, tomato, peppers, onion, lime juice, and a bit of hot chile pepper, distinctively Caribbean ingredients that you probably have in your pantry, come together in a coconut milk base, you end up with a fish stew that's hearty but not heavy. Here in New England the fishmongers sell cod loin, a thick cut of white fish; if you don't like cod, or can't find the loin cut, use salmon, halibut, red snapper or mackerel, whichever looks best at the market. Serve run down as a main course, with rice (for a gluten-free dish) or some crusty bread to mop the bottom of the bowl. Remember: food that comes from hot climates really does cool you down in the summer.