To a small bowl, add the brown sugar, chili powder, garlic powder, cumin, salt, onion powder, and pepper. Mix together, then set aside.
Lay the beef ribs flat on a flat surface and apply 3/4 of the rub to the meaty side. Use your fingers to massage it in, then flip the ribs over and apply the rest of the rub to the other side.
Place the trivet in the bottom of the Instant Pot insert. Pour in the water and apple cider vinegar, then place the ribs on the trivet.
Secure the lid, then set the pressure release valve to “SEAL”. Turn the Instant Pot on and turn off the WARM mode. Set the pressure to HIGH and the timer for 25 minutes. Once the timer goes off, do a natural release for 10 minutes, then carefully do a quick release to vent the rest of the steam.
Once the timer goes off, preheat the broiler on your oven and line a large rimmed baking sheet with aluminum foil.
Use tongs to remove the ribs from the Instant Pot and transfer them to the prepared baking sheet (meaty side up). Brush the ribs with your favorite BBQ sauce and broil for 2-4 minutes, or until the sauce is caramelized. Don’t walk away while the sauce is caramelizing (it can burn quickly).