Turn your Instant Pot onto sauté mode and add in the oil.
Once the oil is hot, add meat in one layer into the pot and sear one side for about 5 minutes.
Next, flip over the meat and sear the other side for 5 minutes. Then remove the meat from the Instant pot onto a plate and set aside.
Add the onion and enough beef broth to cover the bottom of the instant pot and using a wooden spoon, loosen any brown bits at the bottom of the pot.
Next, add the pepperoncini and pepperoncini juice into the pot along with the remaining beef broth, ranch and au jus seasoning packets and butter and stir everything together.
Turn off the sauté mode and add the meat back into the pot.
Close the lid and set your Instant Pot to Seal on the top, then Pressure Cook on High for 1 hour.
Once 1 hour is up allow the pressure to naturally release for 15 minutes before manually releasing.
Remove the meat from the pot, shred it, and set it aside.
Turn the sauté function back on.
While it’s heating mix the flour and butter together to create a thick paste.
Once the Instant Pot is hot, add in the flour mixture and stir until well thickened.
Finally serve and enjoy!
Video
Notes
You can store any leftovers of this Mississippi roast in an airtight container in your fridge for up to 4 days. To reheat you can add in a splash of broth or water and microwave everything until it's warmed through.To freeze you can place the roast in an airtight container in your freezer for up to 3 months. Be sure to thaw in your refrigerator overnight before reheating.