1. Pat the chicken breasts dry with paper towels, then season both sides generously with salt, pepper, garlic powder, and onion powder.

2. Heat the olive oil in a large skillet over medium-high heat until it shimmers. Add the seasoned chicken breasts and cook for 6–7 minutes per side, or until the internal temperature reaches 165°F and the chicken is golden brown. Remove from the skillet and tent with foil to keep warm.

3. Reduce heat to medium and melt the butter in the same skillet. Add the sliced mushrooms and cook for 5–7 minutes, stirring occasionally, until they release their liquid and develop a deep golden-brown color.

4. Sprinkle the flour evenly over the mushrooms and cook for 1 minute, stirring constantly to prevent lumps.

5. Gradually whisk in the beef broth and milk, making sure to scrape up any browned bits from the bottom of the pan. Bring the mixture to a simmer and cook for 3–5 minutes, stirring frequently, until the gravy coats the back of a spoon. Season with additional salt and pepper to taste.

6. Return the chicken breasts to the skillet. Top each breast with about 1/4 cup of the shredded Monterey Jack cheese and spoon the mushroom gravy over and around the chicken.

7. Place the skillet under a preheated broiler (about 6 inches from the heat source) for 1–2 minutes, watching carefully, until the cheese is melted and bubbly with light golden spots.

8. Serve immediately, garnished with crumbled bacon and sliced green onions if desired. Let the chicken rest for 2–3 minutes before cutting.