For the roast beef and gravy:
- 3 pounds beef chuck roast, trimmed of excess fat
- 1 tsp kosher salt
- 1 tsp garlic powder
- 1 cup beef broth
- 1 packet of brown gravy dry mix
For the mashed potatoes:
- 3 pounds Russet potatoes, peeled and cubed
- 1 ½ tsp kosher salt
- ¾ cup milk
- 3 Tbsp butter
- ½ tsp garlic powder
- ¼ cup sour cream
For the sandwich:
- 12 slices of white bread or Texas toast
1Season the beef: Pat the chuck roast with the salt and garlic powder. Pour broth into Instant Pot and place the chuck roast in the bottom of the pot.
2Cook beef: Cover Instant Pot and lock lid into place. Make sure valve is set to sealing. Set the manual/pressure cook button to 70 minutes. When time is up move the valve to venting (quick release).
3Cook potatoes: Open the Instant Pot and place a steamer basket in the pot on top of the beef. Add the potatoes to the steamer basket. (If you don’t have a steamer basket just add the potatoes straight into the Instant Pot). Lock the lid into place, set valve to sealing and set the manual/pressure cook button to 8 minutes. When the time is up let the pressure release naturally for 15 minutes then move the valve to venting. Remove the lid.
4Mash potatoes: Dump the potatoes into a large bowl and mash. Add in the butter, milk, kosher salt, garlic powder and sour cream and stir/mash until creamy and smooth.
5Prepare the gravy: Move the roast to a cutting board and let it rest. Use a fat separator* to strain off the fat from the broth in the Instant Pot. Add strained broth back into the Instant Pot. Turn the Instant Pot to the saute setting. Slowly whisk in the gravy packet. It will start to thicken in a couple of minutes. To make a thicker gravy add in a cornstarch slurry (in a small bowl stir together 1-2 Tbsp of cornstarch with 1-2 Tbsp of water, until smooth.Then pour the mixture into the Instant Pot. The cornstarch mixture will thicken up contents of pot quickly). Salt and pepper the gravy to taste.
6Shred the beef: Cut the roast or shred it up. Season it to taste with salt and pepper.
7Assemble the sandwiches: Toast the slices of bread (optional). Place a portion of roast beef on a slice of bread on a plate. Top the sandwich with another piece of bread. Scoop some mashed potatoes on the plate. Ladle gravy over the top of the sandwich and mashed potatoes. Eat and enjoy!