Combine the chili powder, paprika, oregano, garlic powder, onion powder, red-pepper flakes, salt, and black pepper in a small bowl; stir until evenly blended.
Coat both sides of the chicken tenders with the spice mixture and set them aside.
Warm the olive oil in a large, heavy skillet over medium-high heat. Add the seasoned chicken; sear for 5–6 minutes, turn, and cook an additional 3–4 minutes. Transfer the chicken to a plate and tent loosely with foil to maintain warmth.
Lower the heat to medium. Melt the butter in the same skillet, then add the minced onion and garlic; sauté for 2–3 minutes until just softened.
Pour in the white wine, scraping up the browned bits from the pan’s base. Allow the liquid to simmer for about 5 minutes, reducing slightly.
Stir in the uncooked rice, ¼ cup of the Parmesan, and the chicken broth. Bring the mixture to a gentle boil, then reduce the heat to low, cover, and cook for 20 minutes.
Lift the lid; if the rice has not completely absorbed the liquid, replace the cover and continue cooking for up to 5 more minutes.
Fluff the rice with a fork, arrange the reserved chicken tenders over the top, and scatter the remaining Parmesan and chopped parsley. Serve immediately.