In the electric pressure cooker, press the sauté button and adjust until "more" is highlighted. When the display reads hot, add the diced bacon. Cook the bacon until it is crisp, remove it to drain on paper towels, reserving the bacon grease in the pot.
In a large bowl, add the beef stew meat and salt. Add half of the beef to the Instant Pot and let it sauté until brown. Remove to a plate and add the rest of the beef to sauté until brown.
Hit the cancel button, then add all of the beef to the pot, the onion, carrots, mushrooms, thyme, and beef broth. Be sure to scrape any stuck on burned bits from the bottom of the pot.
Place the lid on the pot, set the valve to sealing, and set to high pressure cook for 35 minutes. When the pot is finished cooking, let the pressure release naturally for 10 minutes, then release the rest of the pressure manually by turning the valve.
Remove the lid, whisk in the Xanthan gum to thicken, and serve in bowls with the reserved cooked bacon on top of each bowl.