Preheat oven to 425°F (220°C) with a sheet pan inside.
In a large bowl, mix chili powder, cumin, 1/2 teaspoon salt, garlic powder, paprika, and pepper.
Set aside 1 teaspoon of the spice mix.
Add 1 tablespoon olive oil to the remaining spices.
Toss chicken, onion, and bell peppers in the mixture.
Carefully remove hot pan, lightly grease, and spread mixture evenly.
Roast for 15 minutes.
Toss kale and black beans with remaining oil and salt.
Remove pan, stir chicken, and add kale and beans on top.
Roast another 5–7 minutes until cooked through.
Mix yogurt, lime juice, water, and reserved spices.
Serve the Sheet Pan Chicken Fajita Bowls drizzled with the yogurt sauce.