Grilled Branzino with Herbed Pearl Couscous

Fish

• 2 whole branzino (about 1 to 1 1/4 lb each), scaled, gutted, butterflied and pin-boned — ask the fishmonger to do this
• 2 tbsp olive oil
• 1 lemon, half sliced into thin rounds, half reserved for serving
• 2 sprigs rosemary
• 4 slice thin slices garlic (optional)
• 1 tsp kosher salt
• ½ tsp freshly cracked black pepper

1. Pull the fish out of the fridge 20 minutes before cooking and pat it bone dry inside and out, then dry it again right before it hits the grate.
2. Score the skin on both sides: shallow diagonal cuts through the skin only, about an inch apart, angled not straight down. You're cutting the skin so it can't contract and curl the fish away from the grate. Going deeper than the skin lets the flesh flake apart when you flip.
3. Season inside and out with the salt and pepper. Lay the rosemary and garlic in the cavity, close the fish, and slide lemon rounds into the scores on the presentation side. Rub the outside with olive oil.
4. Build a two-zone fire or heat a gas grill to medium-high on one side, medium on the other.
5. Start the couscous. Toast it dry in the olive oil over medium heat in a small saucepan for 2 to 3 minutes, stirring, until it smells nutty and the pearls turn a shade darker. Skipping the toast is what gives you gluey couscous.
6. Add the stock and salt, bring to a boil, then cover and drop to low for 10 to 12 minutes until the liquid is gone and the pearls are tender with a slight chew. Take it off the heat and let it sit covered for 5 minutes.
7. While that rests, grill the fish over the hotter zone, presentation side down, for 4 to 5 minutes. Don't move it at all. It's ready to flip when it releases on its own. If you lift a corner with a spatula and it resists, give it another 30 seconds rather than forcing it.
8. Flip once, using a wide spatula and your tongs together, and move it to the medium zone. Cook another 4 to 6 minutes depending on thickness. It's done at 130–135°F at the thickest point, or when the flesh is opaque and separates cleanly at the backbone line. Branzino is lean and goes from silky to dry in about a minute, so pull it at the low end.
9. Finish the couscous: fork in the butter, herbs, lemon juice, and pepper. Taste for salt.
10. Rest the fish 3 minutes off the grill. Plate the couscous, lay the fish alongside, and serve with the reserved lemon and a drizzle of olive oil.