In a medium bowl, whisk together the peanut butter, soy sauce, sambal oelek, Worcestershire sauce, vinegar, and brown sugar.
Heat 1 tablespoon of oil in the Instant Pot set on the sauté function. Add the pork and break it up as it browns, for about 3 minutes. Using a slotted spoon, remove the pork and add to the bowl with the sauce. Drain the fat from the cooker.
Add 1 tablespoon of oil to pot, still set on Sauté. Add the onion and celery and cook for about 4 minutes. Add the ginger and garlic, stirring for a bout a minute.
Add the pork and sauce to the pot. Stir well. Add the past and stir until coated. Add the broth and stir again, until well mixed.
Lock the lid into place and set the venting knob to sealing. Turn off sauté and using manual, set the machine to cook at high pressure for 8 minutes.
Use the quick release method to return the pot to normal pressure. Unlock the lid and stir gently before serving.