In a small bowl, mix garlic powder, parsley flakes, paprika, salt, pepper, dried rosemary and cayenne until well combined. Place potato wedges and chicken on baking sheet.
Drizzle olive oil evenly over chicken and potatoes, tossing to coat. Sprinkle with herb and spice mix, toss again to coat all sides with spices.. Arrange potatoes and chicken on sheet pan into single layer.
Place sheet pan on middle oven rack. Bake 35-40 minutes, until internal temperature of chicken reaches 165° at thickest part of breast and potatoes are tender and golden.