01 - Heat olive oil and 1 tablespoon butter in a large heavy-bottomed skillet over medium heat. Add onions and a pinch of salt; cook until translucent, about 2 to 3 minutes.
02 - Add minced garlic and sliced mushrooms. Stir occasionally and cook until mushrooms are golden and moisture is evaporated, approximately 7 minutes.
03 - Incorporate arborio rice into the skillet and toast for 2 minutes until the edges become translucent.
04 - Pour in dry white wine and stir until fully absorbed by the rice.
05 - Add a ladle of warm vegetable broth at a time, stirring continuously. Wait until most liquid is absorbed before adding the next ladle. Continue until rice is creamy and al dente, about 18 to 20 minutes. Use less broth if needed.
06 - Lower heat. Stir in remaining butter, heavy cream, and Parmesan cheese until melted and creamy. Season with salt and freshly ground black pepper to taste.
07 - Remove from heat. Fold in chopped parsley and adjust seasoning as desired. Serve immediately, garnished with extra Parmesan and parsley.