Roasted Chicken and Potatoes with Herb Sauce

Preheat the oven to 350°F.
In a small bowl, combine melted butter, salt, pepper, rosemary, garlic, and juice of one lemon.
In a large roasting pan, arrange potato wedges in a single layer. Coat potatoes with 1/3 of the butter mixture. Toss to combine.
Place chicken pieces over the potatoes. Rub the rest of the butter mixture onto chicken.
Cut remaining lemon into wedges and arrange over potatoes and chicken.
Roast in oven 1 1/2 hours, or until chicken reaches 170°F.
While the chicken and potatoes are roasting, prepare the herb sauce.
In a small food processor, combine all ingredients. Process just until finely chopped (you don't want a paste!).
When the chicken is cooked, remove from oven. Immediately top chicken pieces with herb sauce and let sit 10 minutes before cutting. Use remaining sauce for serving.