In a mixing bowl, combine the cilantro, jalapeno, ginger, garlic, lime juice, soy sauce, sugar, salt, pepper, and 2 tablespoons of olive oil. Stir the ingredients together until well incorporated.
Place a skillet over medium-high heat and coat with the remaining 2 tablespoons of olive oil. Season the tuna generously with salt and pepper. Lay the tuna in the hot oil and sear for 1 minute on each side to form a slight crust. Pour 1/2 of the cilantro mixture into the pan to coat the fish. Serve the seared tuna with the sliced avocado and the remaining cilantro sauce drizzled over the whole plate.
Recipe courtesy of Tyler Florence