Drain the can of tuna and add it to a bowl. Add the avocado, salt, pepper, garlic powder, lemon juice and mash with a fork until well combined.

Lay the piece of nori out on a clean surface and spread the tuna on one side on the nori, leaving about 1/3" of space on the edge. Top with green onion. Layer the cucumber, carrots, pickled onion next to the tuna.

Roll the nori into a tight roll and slice in half with a knife. Serve the wrap fresh with a side of your choice!