1/3 cup plus 2 tablespoons extra-virgin olive oil 1/2 cup chopped cilantro 1/2 small red onion, minced 1 jalapeño, minced 3 tablespoons sherry vinegar 2 tablespoons chopped basil 2 tablespoons chopped parsley 3 garlic cloves, minced 1 teaspoon chopped thyme 1 teaspoon red pepper flakes 1/8 teaspoon cayenne pepper kosher salt freshly ground black pepper 1 1 - lb sushi -
grade tuna steak 6 oz baby arugula 2 avocados, pitted, peeled and sliced