Preheat the oven to 400ºF.
Mix all of the spices for the fajita seasoning in a small bowl and set aside.
Slice the onion and bell peppers into thin strips. Slice the chicken breast into strips as well. Add the chicken and vegetables to a large baking sheet.
Drizzle the olive oil over the chicken and vegetables and toss to combine. Next, sprinkle the fajita seasoning mix over the top. Mix to fully coat the vegetables and chicken with the seasoning. Spread the chicken and vegetables out over the baking sheet evenly.
Bake the chicken and vegetables in the oven for 35-40 minutes, stirring once halfway through. Squeeze the juice from half of the lime over the top of the chicken and vegetables when they come out of the oven.
To serve, scoop a small amount of meat and vegetables into the center of each tortilla. Add toppings of choice and enjoy!
