Ask locals about the cevice restaurants in the area you are in. Concierges in local hotels are a wealth of information. Have them write you a list of suggestions that are walkable. Make sure to have them give you a list that includes different styles.
Visit these restaurants, or cebecherias, as they are called. Start by ordering appetizers of ceviche, varying the order with different fish. There will be shrimp, lobster, corvina and tuna, as well as others. Typically, they will be served with a side of dried corn kernels and a sampling of hot sauces that accompany them. Write down your opinions and the flavors you taste. Keep track of the ingredients as well. Move on to another restaurant after one round of appetizers.
Order another sampling of cevice at the next restaurant, focusing on entrees and different styles from the other restaurant. Share plates and try different fish. There will be options for spicier ceviche, ones using lime or lemon as the acid in the recipe and ones using boiled sweet potato or corn pieces in them. Some will be drier and use orange juices to "cook" the fish while others will have a fair amount of sauce from other citrus fruits. Some will use tomato or coconut milk as well. Try them at different stops on your cevice tour.
Continue your trek as long as you are hungry. Spread it out over a few days and keep good notes. Sample only one or two dishes in each place, do not fill up on side dishes, and enjoy the fresh seafood of Peru.
