Crispy Chicken and potatoes

2 teaspoons cornstarch
Table salt
1 whole chicken (3 1/2 to 4 pounds), giblets discarded, skin patted dry with paper towels
2 pounds small red potatoes , scrubbed and halved
2 teaspoons vegetable oil

1. Line roasting pan with foil, letting foil come up sides of pan. Adjust oven rack to middle position (8 to 10 inches from broiler element), place roasting pan on rack, and heat oven to 475 degrees. Coat V-rack with cooking spray.
2. Combine cornstarch and 2 teaspoons salt in small bowl. Use skewer to poke holes all over chicken skin. Rub cornstarch mixture evenly over chicken.
3. Remove roasting pan from oven. Place chicken, wing side up, in V-rack, then place V-rack in roasting pan. Roast chicken 15 minutes. Remove roasting pan from oven and, using wad of paper towels, flip chicken so that other wing is facing up. Roast 15 minutes.
4. Meanwhile toss potatoes, oil, and 1/2 teaspoon salt in medium bowl. Remove roasting pan from oven and, with potholder, carefully transfer V-rack with chicken to rimmed baking sheet. Gather up foil by its corners, capturing any fat and juices, and discard. Arrange potatoes, cut side down, in roasting pan. Using wad of paper towels, flip chicken breast side up in V-rack. Place V-rack back in roasting pan and roast chicken until instant-read thermometer inserted into thickest part of thigh registers 170 degrees, about 20 minutes.
5. Using wad of paper towels, remove chicken from V-rack and pour juices from cavity into roasting pan with potatoes. Place chicken on angel-food-cake pan insert or empty soda can to rest upright for 10 to 15 minutes. Meanwhile, toss potatoes in chicken juices, return to oven, and cook until well browned and crisp, 10 to 15 minutes. Carve chicken and serve with potatoes.