Turn on the pressure cooker and select sauté. Once hot, add the bacon and cook 3-5 minutes or until bacon is done. Remove the bacon using a slotted spoon and set aside on a paper towel lined plate.
Add beef & cook until browned, 2-3 minutes on each side.
Add the broth and if needed, deglaze the bottom of the pressure cooker by scraping all the bits off with a wooden spoon.
Add bacon, pearl onions, carrots, mushrooms, potatoes (if using), garlic, salt, thyme, and pepper. Stir to mix well.
Close lid and seal valve. Set high pressure and cook for 35 minutes. When done, natural release pressure for 10 minutes then manually the remaining pressure.