The whole fam can get in on the fun of threading these skewers—and then eating them!
Alternately thread bell pepper, zucchini, onion, and tomatoes onto 4 skewers. Brush with oil; season. Heat grill or grill pan to medium-high. Grill skewers, turning often, until vegetables are tender, about 10 minutes. Grill sausages, turning often, until cooked through, about 10 to 15 minutes. Grill naan until charred in spots, about 2 minutes per side. In bowl, mix yogurt and harissa; garnish sauce with scallion. Serve skewers, sausages, and naan with sauce.