1. Preheat oven to 375 degrees Fahrenheit. Prepare a sheet pan with parchment paper.
2. Drizzle half of the oil over the parchment. Place the onion slices toward the center of the sheet pan. You can put smaller rings loosely inside larger ones.
3. Spatchcock the chicken. (These directions are easy to follow along with my video tutorial on how to spatchcock a chicken – the link will take you to Youtube.) For this, you will need sharp meat shears (found inside most knife block sets). Place the chicken directly in front of you with it’s back up. The back is the side the drumsticks point away from. If your drumsticks are in the air, flip the chicken over. Make sure the legs are toward you, the neck facing away.
4. Now with your fingers, find the spine by placing a thumb inside the cavity. Pinch the spine to steady it while you shear along the side of it. You will hear the ribs cracking and snapping as you go. Cut all the way from one hole to the other. The chicken will now open up a little.
5. Continue to hold on to the spine and shear the other side. Then discard the spine. Take a paper towel and pat out any juices from the inside of the chicken.
6. Generously salt and pepper the inside of the chicken. Then lift the chicken and lay it over the onions on your sheet pan. The legs should turn outward. Salt and pepper the skin of the chicken. Tuck any onions that you can see back under the chicken. Exposed onions will burn.
7. Sprinkle the onion powder, garlic powder, paprika, and mustard powder evenly over the chicken. Then drizzle over the remaining oil. Rub the oil and spice mixture into the skin. Thoroughly wash and sanitize your cooking area and hands.
8. Now in a large bowl, add your pieces of potato and red pepper. Toss. Then add the oil, kosher salt, black pepper and paprika. Toss to evenly coat. Spread the potato mixture around the open areas of the sheet pan in a single layer.
9. Now put your sheet pan in the oven and roast at 375 degrees Fahrenheit for one hour (internal temperature of 165 degrees).
10. Allow the chicken to rest outside of the oven for five minutes while you plate the potatoes, then you can move and carve it up. This allows the juices to return to the meat for a more moist chicken. Serve the onions either mixed in with the potatoes, or as a topping to the chicken.
It’s a one-pan dinner that will feed the whole family. You can freeze or refrigerate leftovers. In order to keep the chicken from drying out, include some of the juices from the pan when packing up the chicken.