Coarsely chop onion and place into a mini chopper or food processor. Blend until until finely minced. Set aside.
To the Instant Pot, add chicken stock and all the chicken breasts and thighs.
Sprinkle chicken with garlic powder and onion powder, drizzle with Worcestershire and liquid smoke.
Add the finely minced onion on top of everything. Sprinkle with brown sugar and top it all with the barbecue sauce.
Close lid and turn vent to the closed position. Cook on high pressure for 20 minutes. Do a 10 minute natural release, then open vent to release any remaining pressure.
Remove lid and spoon off much of the liquid, but reserve it in cases you need to add some back in. Shred the chicken with two forks. If too dry add some of the reserved liquid back in.
TIP - the chicken mixture may drip some of its liquid, making the bottom bun soggy. You can either drain it more and add more barbecue sauce, or line each bottom bun with lettuce before adding the chicken.
Scoop 1/2 cup of chicken onto each sandwich bun. Top with coleslaw if desired.
Notes
We’re using both chicken breast and chicken thighs for this recipe. The mixture of the two goes really well together and the dark meat helps add even more moisture and flavor. You can certainly use all chicken breast if that’s what you prefer.
We're partial to our Dr. Pepper Barbecue Sauce for this recipe, however, any bottled barbecue sauce will do.