How to Make It
Place a rack in center of oven; preheat to 400ºF. Rub carrots with 1/2 Tbsp. oil; season with 1 tsp. cumin, salt and pepper. Arrange in a single layer on a rack in a roasting pan. Whisk together remaining 1 1/2 Tbsp. oil, vinegar, chili powder, garlic, remaining 1 tsp. cumin, 1 tsp. salt and 1/2 tsp. pepper in a small bowl. Rub chicken all over with spice mixture; place onion and lemon wedges in cavity. Tie legs with kitchen string and place on top of carrots on rack. Add 1 cup broth to bottom of pan.
Roast chicken, adding more broth to pan as needed, until carrots are tender, chicken is golden brown and an instant-read thermometer inserted into center of a thigh reads 165ºF, 1 1/4 to 1 1/2 hours.
Let chicken rest for 10 minutes before carving. Squeeze half of lemon wedges into pan juices; discard wedges and onion. Transfer carrots to a serving dish. Skim fat from pan juices. Carve chicken and serve with carrots, pan juices and fresh lemon wedges.