Instant Pot Steak Diane Casserole–a savory sauce with loads of flavor and tender bites of beef and mushrooms. Make in the Instant Pot, slow cooker or the oven!
Add onion, tomato paste, Worcestershire, vinegar and mushrooms and toss well. Turn Instant Pot to sauté. Add broth and boil. Once boiling add meat mixture. Don’t stir. Turn off.
Pressure cook 15 minutes. Let sit 15 minutes and then vent. Stir cornstarch and heavy cream until smooth. Turn to sauté and add the mixture. The sauce will thicken quickly.