Begin by seasoning the pork with 1/2 teaspoon of salt and pepper on each piece. Allow it to rest for 15 minutes to absorb the seasoning.
In the Instant Pot, whisk together the cola, hoisin sauce, ketchup, soy sauce, and brown sugar until well combined. Introduce the dried chile peppers, scallions, and strips of orange zest to the mixture. Next, add the pork to the pot, ensuring each piece is thoroughly coated. Secure the lid and confirm that the steam valve is set to the sealing position. Set the Instant Pot to pressure cook on high for one hour.
Once the cooking cycle concludes, carefully switch the steam valve to the venting position to release the pressure. Afterward, remove the lid with caution. Transfer the pork to a large bowl to cool slightly, and with a slotted spoon, remove and discard the chile peppers, scallions, and orange zest from the cooking liquid.
Switch the Instant Pot to the sauté setting and bring the cooking liquid to a simmer. Skim off any excess fat and allow it to reduce until it thickens lightly, approximately 15 minutes, resulting in about 2 1/2 cups of liquid. Stir in the rice vinegar and adjust the seasoning by tasting and adding more vinegar as necessary.
Shred the pork, discarding any large fatty pieces. Mix the shredded pork with 1 cup of the reduced cooking liquid, adding more liquid as needed for moisture. Serve the pulled pork on toasted sesame hamburger buns, garnishing with coleslaw, cucumber slices, and/or fresh cilantro, alongside additional cooking liquid if desired.
Inspired by the love of squeezing citrus wedges into cola, consider incorporating a citrus-cola sauce that pairs wonderfully with grilled chicken wings.