1 small fennel bulb with feathery stalks
3/4 pound sweet potatoes, peeled and cut into 1/4-in. slices
1 1/4 teaspoons kosher salt, divided
1/2 teaspoon pepper, divided
1 medium red onion, cut lengthwise into 1/3-in.-wide slices
2 large firm-tart apples, such as Ida Red, Sierra Beauty, or Granny Smith, unpeeled, sliced into 1/4-in. wedges
6 bone-in, skin-on chicken thighs (2 3/4 lbs. total)
2 tablespoons margarine, melted
1 teaspoon honey
1 1/2 teaspoons Chinese five-spice
.Preheat oven to 425°. Cut off fennel stalks and reserve feathery leaves. Trim base of bulb and any tough outer layers. Halve bulb lengthwise, cut out core in a V, and cut bulb lengthwise into slim wedges.
Oil a large rimmed baking sheet and arrange sweet potatoes and fennel in a single layer. Sprinkle with 1/2 tsp. salt and 1/4 tsp. pepper. Arrange onion and apples over potatoes and sprinkle with 1/4 tsp. each salt and pepper. Set chicken on top. In a small bowl, combine margarine, honey, five-spice, and remaining 1/2 tsp. salt. Brush onto chicken.
Roast 15 minutes, then tip pan and baste ingredients with juices. Continue to roast until chicken is nicely browned, 15 to 20 minutes more. Baste everything again and scatter reserved fennel leaves on top before serving.