Roll the nori so the oba and uni are all covered. You can roll it in a cigar-like shape or have it more like a ball. Or you can make both and dress up your table setting very nicely.
Dip the roll in the tempura batter and make sure every piece is covered in the batter.
Deep fry the tempura until it turns golden.
Take it out of the oil and let it soak for 5 minutes.