Preheat your oven to 425°F (220°C). Line a large baking sheet with parchment paper or lightly grease it with cooking spray.

Pat the chicken breasts dry with paper towels to ensure better browning. Season both sides with salt, pepper, and 1 tablespoon of olive oil. Sprinkle half of the Italian seasoning, paprika, onion powder, and thyme evenly over the chicken. Set aside.

In a large bowl, toss the peeled and cut potatoes with 1 tablespoon of olive oil, salt, pepper, and the remaining half of the Italian seasoning. Spread the potatoes in a single layer on one side of the baking sheet.

Place the seasoned chicken breasts in the center of the baking sheet next to the potatoes. If using, add lemon slices on top of the chicken and around the potatoes for extra flavor. Roast in the preheated oven for 20 minutes.

While the chicken and potatoes start roasting, toss the broccoli florets with the remaining 1 tablespoon of olive oil, salt, and pepper.

After the initial roasting time, remove the baking sheet from the oven and add the broccoli to the empty side of the pan. Return the sheet pan to the oven and continue roasting for another 10-15 minutes, or until the chicken reaches an internal temperature of 165°F (74°C) and the potatoes are tender and golden.

Remove from the oven and let the chicken rest for a few minutes before slicing. Garnish with fresh parsley if desired. Serve the sliced chicken with the roasted potatoes and broccoli.