Combine rind, juice, salt & vinegar in a mixing bowl. Pour over shrimp & marinate in refrigerator overnight. Line a wok with foil. Sprinkle tea, sugar & cayenne on the foil. Set a rack on top. Cover tightly, turn burner on high. Pot will start smoking as sugar melts. Turn off burner. Place shrimp on rack, re-cover & turn heat back on high. Smoke for 5 minutes. Do not overcook. Will keep 3-4 days in the refrigerator.