Turn on the instant pot and select sauté.
Add 2 tablespoons of butter and let it melt.
Add in onions and sauté for about 2-3 minutes.
Add remaining butter, mushrooms and sauté for 5 minutes while stirring occasionally.
Add in chicken broth, salt and parsley.
Close the lid of the instant pot and switch knob to sealing and press cancel.
Set the instant pot to “Manual” at high pressure for 10 minutes, release the pressure naturally switching the knob to venting.
Open the lid and remove parsley.
Serve and enjoy.