Ingredients:

Ginger-Mustard Glaze:
1/3 cup teriyaki sauce
2 teaspoons minced ginger
1/2 teaspoon minced garlic
1 tablespoon honey
1 tablespoon Dijon mustard
1/2 teaspoon white wine vinegar

Tuna Burgers:
1 1/2 pounds yellowfin tuna, free of any skin or gristle
2 teaspoons minced garlic,
3 tablespoons Dijon mustard
1/2 teaspoon cayenne
1 teaspoon kosher salt
1/4 teaspoon freshly ground black pepper
1/4 cup olive oil
4 fresh hamburger buns with seeds
1/4 cup Japanese pickled ginger,optional

Directions:

Make the glaze:
Combine all the glaze ingredients in a 1-quart saucepan and bring to a boil. Lower the heat and simmer until the glaze coats the back of a spoon, about 5 minutes. Strain through a sieve and reserve in a warm place until tuna burgers are cooked. (The glaze can be prepared up to 2 days ahead and stored, covered, in the refrigerator.)

Make the burgers:
Grind the tuna in a meat grinder or chop with a large sharp knife to the texture of hamburger meat.(Do not use a food processor,which will shred the tuna rather than chop it.) Transfer the ground tuna to a bowl and combine with the garlic,mustard,cayenne,salt,and pepper.Mix thoroughly.Divide the tuna into 4 equal portions.Using your BurgerMate,form into 4 patties. Heat the olive oil in a large skillet over medium-high heat and sear the tuna burgers until browned and medium rare,3 to 4 minutes a side.

Serve each burger on a buttered toasted bun and spread with a tablespoon of warm glaze.Garnish the burgers with equal amounts of pickled ginger slices.