Step 1

Make Dipping Sauce. In a small bowl, combine all the ingredients for the dipping sauce (Yangnyeom Jang). Mix until sugar is dissolved. Set aside.

Step 2

Prep Tuna Steaks. Generously salt and pepper both sides of the tuna steak. Add a thick layer of sesame seeds to each side, coating well so there's no red tuna visible on the top or bottom. Gently pat the sesame seeds so they stick.

Step 3

Heat skillet. Heat a cast iron skillet over medium high heat. When the pan slightly smokes, add 1-2 tsp of oil (neutral oil like grapeseed or avocado oil) and swirl around in the pan.

Step 4

Cook tuna steaks. Add the tuna steaks to the hot pan, being careful of oil splatter. Do not disturb! Cook until the bottom is golden and crusty, about 1-2 minutes. Flip and cook on the other side until golden and crusty, another 1-2 minutes. Be careful not to overcook! Depening on the thickness and size of the tuna steak, adjust the time -- adding more or less time, from as little as 45 seconds up to 2 full minutes per side Look for a red line in the middle that signifies it's rare in the middle.

Step 5

Slice. Transfer to a cutting board. Slice thinly, against the grain, for tuna that's not too chewy or sinewy.

Step 6

Assemble. Add rice to two bowls. Add sliced tuna. Add avocado slices. Drizzle Korean dipping sauce on top of the tuna. Serve with more dipping sauce on the side.