Trim the pork shoulder and cut it into 4 pieces.
Using your hands, rub the dry butt rub into the meat.
Add the olive oil to your Instant Pot set it onto the saute' setting.
Once it is hot, add two of the pieces of the seasoned meat and sear for two minutes on each side. Then remove the seared meat to a platter.
Repeat the process with the last two pieces of meat.
Add 1/2 cup of the chicken broth to the pot to deglaze. Then Press cancel on the pot.
Whisk together remaining chicken stock, barbeque sauce, and liquid smoke.
Place the meat back into the Instant Pot and pour the chicken stock mixture over the meat.
Place the lid on the Instant Pot and be sure the vent is set to sealing.
Set the pot to pressure cook/manual on the high-pressure setting (cook 15 minutes per pound)
Natural release 10 minutes.