In a mixing bowl, combine the yuzu juice, light soy sauce, ground pepper, minced garlic, and finely chopped French shallots. Whisk together until all ingredients are well blended. Gradually add the grape seed oil while whisking continuously to emulsify the dressing.
Using a sharp knife, slice the tuna sashimi into thin, even pieces. Aim for a thickness of about 1/4 inch to ensure a tender bite. Arrange the slices artfully on a plate.
Once the tuna is plated, generously drizzle the yuzu dressing over the sashimi. Make sure to cover each slice for maximum flavor.
Finish off the dish by scattering fresh baby coriander over the top. This not only adds a burst of flavor but also enhances the visual appeal of the dish.
Tuna sashimi is best enjoyed fresh. Serve immediately to savor the delightful flavors and textures.