To prepare the nori shells, cut each nori sheet in half, then trim off the bottom third. Discard the trimmed scraps.
In a wide, deep skillet, pour in about 2 inches of oil and heat over medium. If using a candy thermometer, attach it carefully, ensuring the tip does not touch the bottom of the skillet.
While the oil heats to 350℉. Prepare half the package of tempura mix in a bowl according to the instructions.
When the oil is ready, place one sheet of nori on top of the tempura mix, then flip it over to coat the other side. Immediately and gently place the coated nori into the hot oil.
Use tongs or chopsticks to submerge the nori. Cook for 30-45 second son one side, then flip and cook for another 30-45 seconds or until lightly golden.
Remove and bent to a taco shape (be careful they are hot). Or bend into a paper towel lined taco holder.