Marinated Fresh Anchovies (Alici Marinati)

Using scissors, trim the fins off of all the anchovies. Using a sharp paring knife, slit each fish along the belly from head to tail; remove the entrails and rinse well. Cut off the heads and carefully pull out the spine and pin bones from the top with your index finger and thumbnail. Separate the two fillets and rinse again. Arrange a layer of the fillets in a deep oval gratin dish and sprinkle with a tablespoon or two of vinegar. Continue until all the fish fillets are used, then pour the rest of the vinegar over the fish. Cover and marinate in the fridge for at least 4 hours.
Remove the anchovies from the vinegar, rinse, and pat dry with a kitchen towel. Wash out the dish and dry well. Return a single layer of cured anchovies to the dish and sprinkle with 2 or 3 tablespoons olive oil, a pinch of oregano, a pinch of pepper flakes, a pinch of parsley, three or four garlic slices, and a pinch of salt. Layer in the rest of the anchovies, sprinkling each layer with oil, oregano, pepper flakes, parsley, garlic, and salt. Cover again and marinate in the fridge for at least 2 hours.
To serve, bring anchovies to just below room temperature (in Italy they would be served at about 58°F). Remove from the oil and arrange six or seven on each plate with a lemon wedge if desired.