Start with a fresh piece of seasoned tuna. Give it a quick sear on high heat for no more than a minute on each side. Cut tuna into pieces. Cut up one avocado for every 10ozs of tuna. Add soy sauce, sesame oil, red pepper flakes, toasted sesame seeds, scallion, and cilantro. Allow to marinate for thirty minutes. Squeeze a lime over top and you're ready to rock. Can't beat fresh seafood!