Sear the roast:

• Set Instant Pot (IP for short) to saute & add 3-4 T of olive oil. While the oil heats up, cut the roast in half (if needed) to fit in the bottom of the pot. When the oil is hot, sear the roast for 5 minutes per side. Add more oil if needed & repeat with the second half. Remove from pot & set aside after all sides are browned.
• Deglaze the bottom of the pot with a wooden or plastic spoon; remove all the bits from the bottom. Add 1/4 cup of water if you need more moisture to loosen the stuck on bits. Add 3/4 cup of the brine from the pepperoncini jar to the pot, along with 1/2 cup of water. (You can do more brine & less water if you prefer; it will be spicier.) Add the ranch & gravy packets; stir until it is all mixed well.
• Add roast back to the pot, nestling down side by side if possible to submerge as much of the meat as possible. Cut the stick of butter into pads, about 1/3-1/2 T per pad. Evenly spread the butter out on top of the meat. Use at least half of the pepperoncini's from the jar, laying them on & around the roast. The more you add, the spicier it will be.
• Place the lid on the instant pot & seal the valve. Cook on manual pressure for 50 minutes. Let naturally release for 10 minutes before venting the seal & releasing the rest of the pressure. Once the pin drops in the lid indicating pressure is down, remove the lid.
• Carefully remove the meat; it may fall apart easily. Skim as much fat from the top as you can or prefer. I like to use bread or paper towel to easily soak it up. Once the fat is skimmed, return the meat to the pot & break it up or shred it as desired.
• Enjoy!