If you do not have thin fillets, cut thin scallop slices from a big fillet, and slice them at a 45-degree angle into ½-inch pieces.
Puree the marinade ingredients in a blender or food processor. Strain the marinade over the fish, brushing to coat the fillets. Marinate them for at least 20 minutes.
Drain the fillets and pat them dry. Dip each piece into the beaten egg.
Coat one side of each fillet with the white seeds.
Coat the other side with the dark seeds.
Heat the oil in a wok until it is moderately hot (about 350 degrees). Holding the pieces with long chopsticks, dip them into the oil one at a time for a few seconds, just long enough for the coating to set and the surface of the fish to turn opaque.
Just before serving, fry them all together for about 2 minutes. Arrange them to show off the contrast of light and dark seeds.
Fillets can be marinated ahead of time and deep-fried at the last minute.