Spread the tuna, scallions, olives and capers on a plate and freeze for 5 minutes. Transfer to a food processor and pulse until the tuna is finely chopped. Transfer the mixture to a bowl; season with salt and pepper. Form the mixture into four 4-inch patties.
Light a grill or preheat a grill pan. Brush the burgers with olive oil and grill over moderately high heat, turning once, until golden and crusty and just cooked through, about 6 minutes.
In a bowl, mix the mayonnaise and anchovy paste; spread on the buns. Top with the burgers, tomato and arugula, close and serve.
You May Like
Sign Up for Our Newsletter
Keeping you in the know on all the latest & greatest food and travel news, and other special offers.