Tuna Burgers with Wasabi Ginger Mayo

Name: Tuna Burgers with Wasabi Ginger Mayo
Ingredients: Tuna Burgers; 4 scallions, white and light green parts only, finely chopped; 1/4 cup minced fresh ginger; 1 large egg, lightly beaten; 1 1/2 pounds sushi-grade ahi tuna, chopped; Salt and freshly ground black pepper; 1 English cucumber; 1 tablespoon grapeseed oil; 1 box broccoli or alfalfa sprouts; 6 brioche rolls; Wasabi Ginger Mayonnaise; 1/2 cup mayonnaise; 2 tablespoons prepared wasabi; 6 tablespoons finely chopped pickled ginger (the pink, sweet kind you get with sushi)