Chilean Sea Bass with Peanuts and Herbs

Preheat oven to 350 °F. Whisk lime juice, fish sauce, sugar, and 2 tablespoons water in a small bowl until sugar is dissolved. Set lime juice mixture aside. Heat 2 tablespoons oil in a large ovenproof skillet over medium-high heat. Season fish with salt and cook, skin side down, until skin is golden brown and crisp, 5 –8 minutes. Transfer skillet to oven and roast until fish is just opaque in the center, 5 –10 minutes longer, depending on thickness. Transfer fish to a plate. While fish is roasting, heat remaining 2 tablespoons oil in another large skillet over medium-high heat. Add shallots, ginger, scallions, and chiles and cook, stirring often, until beginning to brown, about 3 minutes. Add garlic and cook, stirring, until golden brown, about 30 seconds. Add reserved lime juice mixture to skillet and cook, stirring, until slightly reduced, about 1 minute. Remove from heat and mix in herbs and peanuts. Serve fish topped with sauce and dill.