Remove any giblets from chicken then rinse chicken with water, inside and out, and pat dry with paper towels.
In a small bowl, combine creole seasoning, bouillon powder, salt, and pepper.
Rub inside and out the chicken with the spice mix. Try to get some seasoning under the skin as well.
Stuff the chicken with 3 smashed garlic cloves and lemon, then refrigerate until ready to cook. If time permits, do it the night before. (up to 24 hours is best).
In a 6- or 8-quart Instant Pot press the saute function.
Once hot, add oil and sear the whole chicken, breast side down for about 3-4 minutes. Then flip and sear the other side. Take the chicken out.
Add 1 tablespoon of oil and saute chopped onion, remaining garlic (minced), celery, and bay leaves.
Pour in the chicken stock and stir, making sure to scrape the bottom of the pot to remove any stuck pieces.
Add potatoes, carrots, thyme, and rosemary. Place the trivet inside of the Instant Pot.
Place chicken back inside on the trivet and close the lid with the vent set to sealing.
Cook on manual high pressure for 24 minutes (or 6 minutes per pound). It will take about 10 minutes for the Instant Pot to come under pressure. The timer starts after this.
When the time is up, let the Instant Pot Pressure release naturally for 15 minutes, then turn the knob to venting to release any remaining pressure.
Let the chicken sit for 10 minutes before carving so the juices settle back into the meat.
Discard bay leaves, thyme, and rosemary sprigs smashed garlic and lemon.
Serve with potatoes and carrots.