01 -
Melt the butter or heat olive oil in a large skillet over medium heat. Add the chopped onion and cook, stirring occasionally, until softened, about 3 to 4 minutes.
02 -
Stir in the minced garlic and cook for 1 minute until fragrant, taking care not to let it brown.
03 -
Add the sliced mushrooms and dried thyme or Italian seasoning. Sauté until the mushrooms release their liquid and begin to brown, about 7 to 8 minutes.
04 -
If using, pour in the white wine and allow it to simmer until almost fully evaporated, approximately 2 minutes.
05 -
Reduce the heat to medium-low, then pour in the heavy cream. Stir well and bring to a gentle simmer.
06 -
Add grated Parmesan cheese, salt, and black pepper. Stir continuously until the cheese melts and the sauce thickens slightly, about 2 minutes.
07 -
Toss the finished sauce with hot cooked pasta. Serve immediately, garnished with fresh chopped parsley if desired.