Press both triangle tuna shapes into sesame seeds, using a good amount of pressure, but being careful not to flatten tuna.
Place in hot sesame oil. Cook to desired temperature (medium rare will take about 4 minutes, depending on whether you have a gas or electric range). Make a small incision in tuna to check doneness.
Reserve hot sesame oil, and in same pan, add soy sauce, jelly, plum sauce and blueberry pulp, and whisk until well-combined. Drizzle over tuna, place over sauteed spinach, serve and enjoy!