Saute mushrooms, onion and garlic in olive oil with marjoram, salt and black pepper in the instant pot using the saute setting for 10-15 minutes or until onions are translucent.
Add remaining ingredients except steak and potatoes and stir.
Place lid on cooker and set the vent to seal.
Shut off the Instant Pot and restart on the Manual setting.
Cook at pressure/high for thirty minutes.
Use the quick release and open when cooker stops venting steam.
Stir in the steak and potatoes and allow to warm in the soup without cooking further.