A whole roast chicken goes a long way, especially if you’re feeding a picnic crowd. Roast the chicken the day or morning before your picnic, then use the different parts for several different dishes. It’s an easy preparation that leaves your hands free for a glass of wine once you’re on the picnic blanket. Preheat oven to 425°F.
Clean the chicken, removing any giblets from the cavity. Rinse with cold water and pat dry. Place chicken, breast-side up, in a large roasting pan, and season cavity with salt and pepper. Cut 1 lemon into quarters, and place inside cavity with 2 sprigs of rosemary. Smash 2 cloves garlic and place in cavity as well.
Brush skin well with two-thirds of the olive oil. Season with salt and pepper.
Clean remaining rosemary off sprig, mince remaining garlic, and combine in a small bowl with remaining lemon juice and potatoes. Season with salt and pepper and toss to coat. Place in roasting pan around chicken.
Roast in oven for 15 minutes until skin is crisped and browned, then reduce oven temperature to 375°F, and roast for another 30-40 minutes, basting chicken and potatoes frequently. Make a small cut between the thigh and the leg to check for doneness. The juices should run clear.
Remove chicken from oven and let cool before carving.