Combine sweet potatoes, chickpeas, 2 tablespoons evoo, ¼ teaspoon cinnamon, salt and pepper to taste. Spread evenly on a sheet pan, roast at 425°F for 20 minutes.
Toss chicken with 1 tablespoon evoo, za’atar, garlic, remaining cinnamon and lightly season with salt and pepper.
Heat 2 tablespoons evoo in a large pan over medium-high heat until oil shimmers. Saute chicken for 3 minutes, flip, add broth and cover. Cook for an additional 5 - 7 minutes until juices run clear and the internal temperature is 165°F. Remove chicken and slice.
Toss chard with lemon zest and juice and season with salt and pepper.
Divide chard between bowls and top with warm sweet potato hash and chicken. Drizzle with tahini.