Heat the oven hot. Position a rack in the upper third of the oven and preheat to 425°F. Line a large rimmed sheet pan with foil or parchment for easy cleanup. The high heat is what gives you char and caramelization instead of steamed, pale vegetables.

Season everything. In a large bowl, combine the chicken strips, bell peppers, and onion. Drizzle with olive oil and lime juice, then sprinkle over the chili powder, cumin, smoked paprika, oregano, garlic powder, salt, and pepper. Toss thoroughly with your hands until every piece is evenly coated. Do not be shy here. Under-seasoned fajitas are a tragedy.

Spread it out. Arrange the mixture on the prepared sheet pan in a single layer with a little breathing room between pieces. Crowding steams instead of roasts. If your pan is small, use two pans. This single detail makes the biggest difference in the final result.

Roast. Bake for 18 to 22 minutes, tossing once halfway through, until the chicken is cooked through (165°F internally) and the vegetables are tender with charred edges. If you want extra char, switch the broiler on for the last 2 to 3 minutes and watch it closely.

Finish and serve. Squeeze fresh lime juice over the hot pan and scatter with cilantro. Serve immediately with warm tortillas and your favorite toppings. The sizzle when it hits the table is half the fun.