Place scallops in stainless steel bowl and marinate for 1 hour in the refrigerator.
Drain the scallops, cut them into quarters, and reserve 1 tablespoon of the juice. Add the remaining ceviche ingredients and the reserved juice. Chill for a minimum of 30 minutes.
To make boats, cut 3-inch rounds from standard-size tortillas. Deep-fry them in 375° oil for 30 seconds. To obtain shape, place the tortilla in a 2-ounce ladle and use a spoon to hold in place while submerging it in to the oil. Drain on paper towels. You can omit these steps if you want to avoid a mess. The scoops-style premade tortilla chips also make the perfect-size tostada boat.
Garnish each emerald boat with a cilantro leaf flag.