For the Paste - Mix the ingredients together and let it sit at least 30 minutes to bloom.
For the Chicken and Potatoes - Position a rack in the middle of the oven and crank the heat to 425°F.
Pat the chicken dry, then wiggle your fingers under the skin to release it from the meat, being careful not to rip it. Using your fingers, rub 4 tablespoons of the paste under the skin of the chicken and inside the cavity. Smear the remaining tablespoon over the outside of the bird.
Tie the legs together and tuck the wing under. Season with salt and pepper. Place the chicken breast-side down on a V-rack in a foil-lined roasting pan.
Toss the potatoes in a bowl along with 4 tablespoons of the paste, the oil, and season with salt and pepper. Scatter them in the pan under the chicken
Roast the bird for 35 minutes, then, using tongs, turn breast side up. Toss the potatoes well to coat with the drippings. Baste the chicken with the last of the paste.
Lower the heat to 350°F and continue roasting until an instant-read thermometer inserted in the thickest part of the thigh reads 165°F, 50 minutes to 1 hour more (longer if the chicken came from the refrigerator).
Remove the bird, cover loosely with foil, and let sit for 10 minutes. If the potatoes aren’t tender, toss again, raise the oven to 450°F, and finish roasting them while the bird rests.
Notes - The paste recipe makes 1 cup. Store the rest in the refrigerator in a jar for a week. Add to sauce for pasta, mix into ground meat for meatballs or toss with veggies before roasting.