Heat the oven: Preheat to 425°F (220°C).
Line a large rimmed sheet pan with parchment or foil for easier cleanup.
Prep the chicken and veg: Thinly slice the chicken. Cut peppers into strips and the onion into wedges. Pat the chicken dry with paper towels so it browns better.
Mix the spice blend: In a small bowl, combine chili powder, cumin, smoked paprika, garlic powder, onion powder, oregano, salt, and pepper.
Season everything: On the sheet pan, toss chicken, peppers, and onion with olive oil and the spice blend.
Spread into an even layer, leaving space so they roast instead of steam.
Roast: Bake for 18–22 minutes, stirring halfway, until the chicken is cooked through and the edges of the peppers start to char slightly.
Add lime: Squeeze fresh lime juice over the hot chicken and veggies. Toss to coat for a bright, fresh finish.
Warm the sides: While the pan roasts, heat the rice, black beans, and corn. Season the beans and corn with a pinch of salt, pepper, and a squeeze of lime if you like.
Assemble bowls: Start with a base of rice.
Add a generous scoop of the fajita chicken and veggies. Top with black beans, corn, avocado, cilantro, salsa, and a dollop of sour cream or Greek yogurt. Finish with cheese or hot sauce if you want.
Taste and adjust: Add a pinch of salt, an extra squeeze of lime, or more salsa.
Small tweaks make a big difference.