Add the tilapia fillets to the bowl and gently turn them over to coat with the marinade. Let the fish marinate for about 5 minutes.
Spray the grill with cooking oil. Take a tilapia fillet out of the marinade, gently shake off the excess liquid and place the fillet on the grill. Repeat for the other fillets. (12 ozs will likely be 3 fillets).
Grill for 3 minutes on one side, then flip the fillets to grill for 3 to 4 minutes on the other side. Use a grill spatula to remove the tilapia from the grill to a platter. Enjoy with a salad and grain side.