Remove the giblets from the chicken and discard them. Dry the inside and outside with paper towels. Massage the cavity with ½ teaspoon salt and ¼ teaspoon pepper. Add sprigs of rosemary, thyme, garlic cloves, and lemon wedges to the cavity. Tuck the wings back and tie the legs together with butcher's twine (optional).
In a small bowl, combine 2 tablespoons olive oil, 2 teaspoons salt, garlic powder, onion powder, paprika, oregano, thyme, and ¼ teaspoon black pepper.
Place the chicken on a plate breast-side down. Brush the seasoning mixture over the bottom. Flip and brush the breast, wings, and thighs. If desired, rub additional salt (1/4 teaspoon) and pepper (1/8 teaspoon) under the skin of each breast
In a 6-quart Instant Pot, select the highest “Saute” setting. Allow to heat and it will indicate "Hot" on the display when ready. Add 1 tablespoon of olive oil. Once hot, add the chicken breast-side down and cook until golden brown, 5 to 6 minutes. Use tongs or a wooden spoon inserted in the cavity to flip the chicken over. Using another spoon on the other side, or your free hand, is helpful for flipping. Cook until browned, 5 to 6 minutes. Transfer to a plate. Press "Keep/ Warm/Cancel".
If there are any charred spices on the bottom of the pot insert, carefully wash and dry before moving forward. Then pour in the chicken stock, scrape the bottom to remove any browned bits, if needed. Place the metal trivet inside and place the chicken on top, breast-side up.
Make sure that the release valve is in the "Sealing" position. Place the lid on, turn and lock.
Press the "Manual" button to high pressure, and then set the timer to 24 minutes using the "+" or "-" controls. See notes on adjusting time per pound.
It will take about 10 minutes for the pot to heat up and build pressure. You will see steam release from the lid, and then the time will start on the display.
Once cooking time is complete, allow the pressure to release for 10 minutes naturally.
Use an oven mitt or towel to gently twist the steam release handle on the lid to the "Venting" position. The initial release will spray some moisture around, so be careful.
Remove the lid, opening the top away from you as steam releases from the pot.
The thickest part of the breast should reach 160 to 165ºF (71 to 74ºC), and thighs 170ºF (74ºC). If it needs more time, cook for another 3 minutes, or until fully cooked.
Transfer the chicken to a cutting board and allow it to rest for at least 10 minutes.
Transfer drippings to a measuring cup. Add additional chicken stock until the volume reaches 2 cups.
To make the gravy, select the normal "Saute" setting. Add the butter. Once melted, whisk in the flour. Whisk and cook until pale yellow roux forms, about 1 to 2 minutes. Gradually whisk in 2 cups of the drippings. Continuously whisk until thickened, about 1 to 2 minutes. If desired, add more chicken stock to thin the sauce, although it will thicken more as it cools—season with salt and pepper.
Once the chicken has rested, carve it into smaller pieces and slices. Serve with lemon wedges and gravy on the side.
Notes
Quicker Preparation: Omit the step on sauteing the skin.
Chicken Cook Time: 6 minutes per pound.
For Crispy Skin (optional): Place chicken on a foil-lined baking sheet after pressure cooking. Brush the surface with olive oil. Set in the lower middle of the oven and broil, for about 5 to 8 minutes. Keep a close eye to prevent burning!
Make it Gluten-Free: Substitute cassava flour or cornstarch for all-purpose flour. If using cornstarch, dissolve 2 tablespoons in a ¼ cup of water. Add to chicken stock and then stir and cook on the saute function until the liquid thickens.