For ceviche, acid does the cooking instead of the oven. In this Latin American-inspired dish, raw fish is marinated in citrus juice, and its acids cook the meat proteins without heat. Chop a fillet of firm-fleshed fish such as snapper, halibut or sea bass (shrimp and scallops are also great) and let it marinate in the refrigerator in a mixture of citrus juice and seasonings. After an hour or two, the fish will be opaque and ready to eat. Serve over salad greens, wrapped in tortillas or with chips for scooping. A few slices of avocado and some salsa are delicious accompaniments.