Once tomatoes and basil are in season this is a wonderful way to serve simple roasted or grilled fish. I serve it often on weekends when we have a houseful of guests. If you prepare the tomatoes before you start cooking the fish the flavors have a little time to meld. Dice 3 tomatoes into 1/2 inch chunks. Chop basil leaves from 3 or 4 sprigs of basil and add to tomatoes. Remove pits from about 1/2 cup olives (nicoise or calamata are good choices), halve them, and add to tomatoes. Add 1 clove of garlic, minced, the juice of 1 lemon and a pinch of sea salt and set aside. Drizzle olive oil on 3 pounds of cod or striped bass on a sheet pan and roast in a 450° oven for about 10 minutes, or until fish is flaky and cooked through. It can also be grilled -- if you choose to grill, buy fish with the skin on and cook skin side down, with the lid on for about 10 minutes. Spoon tomato mixture over fish and serve.