Pre-Roast the Potatoes
Preheat your oven to 425°F (220°C). Toss your quartered potatoes with olive oil, garlic, parmesan, salt, and pepper. Spread them across the pan (lined with parchment paper for easy cleanup!) and bake for 15 minutes. This gives the potatoes the "head start" they need to get soft inside and crispy outside.
Prepare the Chicken
While the potatoes roast, toss your chicken breasts in a bowl with olive oil, parmesan, breadcrumbs, garlic, salt, and pepper.
Layer the Tray
After the first 15 minutes, slide the potatoes to one-third of the pan. Place the seasoned chicken in the middle third. Return the pan to the oven.
Add the Greens
Toss your green beans with garlic, salt, and pepper. Add them to the final third of the sheet pan.
Final Roast
Bake everything together for about 25 minutes. The dinner is ready when the chicken reaches an internal temperature of 165°F (74°C).
For the Perfectionist: If you want ultra-crispy potatoes, remove the chicken and beans once done and broil the potatoes on high for an extra 3–4 minutes.
Rest and Serve
Let the chicken rest for 5 minutes before slicing. This keeps the juices inside rather than on the plate!