Preheat your oven to 400 degrees Fahrenheit. Line a large sheet pan with parchment paper or aluminum foil for easy cleanup.
Prepare the potatoes. In a large bowl, toss the halved baby potatoes with olive oil, salt, pepper, garlic powder, and paprika. Spread them in a single layer on the sheet pan.
Roast the potatoes first. Place the sheet pan in the oven and roast the potatoes for 15 minutes.
This gives them a head start so they get crispy.
Make the garlic butter sauce. In a small bowl, mix the melted butter with the minced garlic. Set aside.
Season the chicken. While the potatoes roast, season the chicken pieces with a pinch of salt and pepper. In the same bowl you used for potatoes, toss the chicken with half of the garlic butter sauce.
Add the chicken to the pan. After 15 minutes, remove the sheet pan from the oven.
Push the potatoes to one side and add the chicken pieces in a single layer on the other side. Drizzle the remaining garlic butter sauce over the chicken.
Finish cooking. Return the pan to the oven and bake for another 15 to 20 minutes, or until the chicken is cooked through (internal temperature of 165 degrees Fahrenheit) and the potatoes are golden and crispy.
Add parmesan and serve. In the last 5 minutes of baking, sprinkle the grated parmesan cheese over the potatoes. Once done, garnish with fresh parsley and serve immediately.