Preheat your oven to 400 degrees Fahrenheit (200 degrees Celsius). Line a large, rimmed baking sheet with parchment paper for easier cleanup.
In a large bowl, combine the quartered potatoes, olive oil, 1 tablespoon of the lemon pepper seasoning, oregano, garlic powder, salt, and black pepper. Toss until the potatoes are evenly coated.
Spread the seasoned potatoes in a single layer on the prepared baking sheet.
In the same bowl, toss the chicken pieces with the remaining 1 tablespoon of lemon pepper seasoning.
Arrange the seasoned chicken pieces among the potatoes on the baking sheet, ensuring everything is in a single layer without overcrowding.
Place the thin lemon slices over the chicken and potatoes.
Bake for 25 to 30 minutes, or until the potatoes are tender and the chicken reaches an internal temperature of 165 degrees Fahrenheit (74 degrees Celsius).
Remove from the oven, garnish with fresh parsley, and serve directly from the pan.
Notes
For crispier potatoes, you can toss them with the oil and seasoning 10 minutes before adding the chicken to the pan.
If you use bone-in chicken pieces, increase the cooking time by 10 to 15 minutes.
Use fresh lemon juice over the finished dish for an extra bright flavor burst.