Cook the whole wheat penne pasta according to package instructions until al dente. Drain and set aside.
In a small bowl, combine chili powder, ground cumin, smoked paprika, dried oregano, cayenne pepper, salt, and black pepper. Mix well to create the fajita seasoning.
Heat olive oil in a large skillet over medium-high heat. Add the sliced chicken breast and sprinkle half of the fajita seasoning over it. Cook for 5-7 minutes, stirring occasionally, until the chicken is cooked through and lightly browned. Remove chicken from skillet and set aside.
In the same skillet, add the sliced onion, red bell pepper, green bell pepper, and yellow bell pepper. Cook for 5 minutes, stirring occasionally, until the vegetables are tender-crisp.
Add the minced garlic and remaining fajita seasoning to the vegetables. Cook for 1 minute until fragrant.
Return the cooked chicken to the skillet with the vegetables. Pour in the chicken broth and fresh lime juice. Stir to combine and cook for 2-3 minutes until the sauce slightly reduces.
Add the cooked pasta to the skillet and toss everything together until well combined and heated through.
Remove from heat and sprinkle chopped fresh cilantro over the pasta. Serve immediately.