Set your pressure cooker to saute and add 2 tablespoons of butter.
Once pressure cooker is hot and butter is melted, season your roast with garlic salt, and pepper. Place roast into the pot and sear roast on both sides.
Once the roast is seared, remove it from the pot and set it aside on a plate.
Keep the pressure cooker on saute, and add one cup of water and 1 teaspoon of Better Than Bouillon beef base. Stir until combined, scraping up any brown bits on the bottom of the pot.
Turn the pressure cooker off. Add the roast back to the pot along with your potatoes and baby carrots. Sprinkle onion soup mix all over the top.
Lock lid of pressure cooker in place. Move pressure valve to sealing. Set Instant Pot to high pressure (Manual) for 90 minutes.
Once the 90 minutes is up, let pressure cooker natural release for 10 minutes. Then quick release any remaining pressure.
Remove roast from pot and transfer to a cutting board. Use two forks to shred the roast, or a serrated knife to cut it into slices. Transfer to dinner plates or a serving platter.
Remove potatoes and carrots from pressure cooker using a slotted spoon. Plate with pot roast. Spoon some of the pan juices over the roast and veggies. Sprinkle with chopped parsley for garnish, if desired.*If you like, use the pot juices to make a gravy right in the pressure cooker using the saute setting, some butter, and cornstarch slurry.
Notes
I like a bone-in chuck roast for the extra flavor it adds. If you can't find bone-in, a boneless roast will work just as well.You can use small red potatoes in place of Yukon gold potatoes if needed.