How to Make It
Whisk together olive oil, dill, chives, lemon zest, salt, and pepper in a small bowl. Pour half of mixture into a 13- x 9-inch baking dish. Add arctic char in a single layer, and spoon remaining olive oil mixture over top. Cover with plastic wrap, and refrigerate at least 3 hours or up to overnight.
Preheat oven to 350°F. Let fish stand in marinade at room temperature 15 minutes before baking. Remove plastic wrap, and bake in preheated oven until fish is just cooked through, 15 to 20 minutes. Cut each fillet into 3 pieces, and serve immediately with cucumber salad and rice.