INGREDIENTS (serves 4)

For the sauce: 
3 cups whole grain mustard
3 cups tamari shoyu
¼ cup rice vinegar
¼ cup mirin
For the blackening powder:
2 sheets of nori
½ cup bonito flakes
1 tbsp togarashi
1 tbsp sesame seeds
For the bluefin tuna: 
12 oz bluefin tuna belly
For the rice: 
2 cups Japanese sushi rice steamed
Maldon salt


Preheat oven to 300ºF. Mix all the ingredients together in a sauce pot and place on stove to get warm (bring the sauce to about 180ºF).

Blackening powder
Grind and fround all the ingredients in a spice grinder and swap out the finished powder to a plate ready to go.

Bluefin tuna
Cut the tuna into four equal three ounce portions. Coat with powder and "burn" in a hot pan on all sides (only one piece of toro will be blackened so as not to cool the pan down). Drop tuna in the hot sauce, place it in the oven and cook until warmed through for about 5 min. A swap out of cooked product will be removed and placed on counter.

After removing the tuna, place the rice in four bowls and slice each piece of tuna and arrange on top of rice. Garnish with grilled scallions and shitake mushroom. Sprinkle with maldon salt.