First, begin by dicing the onion and red bell peppers setting them aside in a separate bowl.
Next, with a sharp knife, slice the beef into cubes or thick strips, however you'd like to present them.
In a large mixing bowl mix the flour, corn starch, salt, and pepper. Dredge the beef cubes/slices in the flour mixture.
Now, turn the Instant pot to Sauté on high for 20 minutes and add the olive oil allowing the pressure cooker to heat up.
Add the dredged beef to the instant pot in two batches browning each side. Once all the beef is browned remove it from the Instant pot and set aside.
Next, pour the beef broth into the Instant Pot and using a stiff spoon or spatula, deglaze the pot.
Sauté the diced onion, bell peppers, and mushrooms for about 6-8 minutes in Instant Pot or until they've began to soften and the onions are turning translucent.
Add in the garlic, stir to incorporate and sauté for about two more minutes or until the garlic is fragrant.
Pour the canned tomatoes, condensed tomato soup, and drained green beans into the pot giving it a good couple of stirs to mix it all up.
Secure the lid and set the Instant Pot to Pressure Cook, High, for 30 minutes and allow for a 10 minute natural release, releasing the remaining pressure manually.
Stir in your chosen thickener and allow it to thicken for about 10 minutes.
Serve over and enjoy!