SERVES 4

Roasting a whole fish on a bed of celery ribs allows the heat to circulate freely underneath the fish and also prevents the skin from sticking to the pan.

1 lemon
1 whole cleaned striped bass (about 2 lbs.)
3⁄4 cup plus 1 tbsp. extra-virgin olive oil
Kosher salt and freshly ground black pepper,
   to taste
1⁄2 cup chopped flat-leaf parsley leaves, stems
   reserved
2 tbsp. chopped tarragon leaves, stems reserved
3 inner ribs celery, halved crosswise
1⁄2 cup chopped celery leaves
1⁄4 cup capers, rinsed and chopped
1⁄4 cup crème fraîche
4 tsp. dijon mustard
6 scallions, white and light green parts only,
   thinly sliced
Large pinch of crushed red chiles

1. Heat oven to 400°. Grate zest from lemon into a bowl. Halve lemon lengthwise. Squeeze juice from 1 half over zest; cut remaining half into thin half moons; set aside. Cut 2 angled crosswise slits on each side of fish, about halfway to bone and 2" apart. Rub fish with 2 tbsp. oil; season it inside and out with salt and pepper. Place 1 lemon slice in each slit; put remaining slices into belly cavity with reserved stems of parsley and tarragon.

2. Grease a baking sheet with 1 tbsp. oil; arrange celery ribs on top to make a rack for fish. Drizzle with 2 tbsp. oil; top with fish. Roast until cooked, 20–25 minutes. Meanwhile, mix together reserved zest and juice, remaining oil, parsley, tarragon, celery leaves, capers, crème fraîche, mustard, scallions, chile flakes, and salt and pepper in a bowl to make salsa verde. Carve fish (following the steps in Carving Whole Fish). Serve with salsa verde on the side.