Preheat your grill to medium heat (between 350 degrees F and 375 degrees F). Liberally coat your fish basket or tray with nonstick cooking spray and place it on the grill to get hot.
Give the branzino a quick rinse under cool running water and rinse the inside and outside of the fish. Pat the fish dry with a paper towel.
3 whole branzino fish
Drizzle the olive oil over both sides of each fish, then generously season the insides and outsides with salt and pepper.
⅓ cup olive oil, kosher salt, black pepper
Stuff the cavities of the branzino with lemon slices, smashed garlic cloves, and parsley. If the branzino is large and fleshy, use a sharp knife to cut slices into the sides of the fish so the thicker parts cook evenly with the thinner parts.
12 cloves whole garlic, 1 cup fresh parsley, 1 lemon
Place the fish onto your hot grill tray/baskets and cook for five minutes. Use a fish spatula to carefully flip the fish and grill the other side for another five minutes. You're looking for cloudy eyes that have shrunken up and crispy skin!
Remove the fish from the grill and serve on a platter with sides.