Preheat oven to 425°. Heat oil in a large ovenproof skillet over medium-high heat.
Season chicken with salt and pepper. Working in 2 batches, cook until browned, about 5 minutes per side; transfer to a plate.
Pour off all but 1 Tbsp. drippings from pan. Add onion and garlic; cook, stirring often, until softened, about 3 minutes.
Add tomato paste and cook, stirring, until beginning to darken, about 1 minute.
Add chickpeas, harissa, and broth; bring to a simmer.
Nestle chicken, skin side up, in chickpeas; transfer skillet to oven. Roast until chicken is cooked through, 20–25 minutes. Top with parsley and serve with lemon wedges for squeezing over.
Recipe by Weekend Table at https://weekendtable.com/2015/02/23/roasted-chicken-with-harissa-chickpeas/