Heat the olive oil and butter in a large skillet over medium-high heat until the butter is melted.
Add the sliced mushrooms, dried parsley, and onion powder to the skillet and cook for about 4-6 minutes until they are golden and have released their moisture.
Add the minced garlic to the mushrooms and cook for another minute until fragrant. Pour in the white wine, scraping any bits off the bottom of the skillet, and cook until the wine has mostly evaporated.
Stir in the chicken broth and heavy cream. Bring to a simmer and cook for about 5 minutes until the sauce thickens slightly. Remove from heat and stir in Parmesan until well blended.