Heat oil a large skillet over medium-high heat. Season salmon with salt, pepper and garlic powder all over. Sear in the hot pan, flesh-side down first, for 5 minutes on each side, or until cooked to your liking. Once cooked, remove from the pan and set aside.
Melt the butter in the same skillet. Sauté garlic until fragrant (about 30 seconds). Pour in the white wine or broth; allow to reduce to half while scraping any bits off of the bottom of the pan.
Reduce heat to low-medium heat, add the cream and bring to a gentle simmer, while stirring occasionally. Season with salt and pepper to your taste.
Add the parmesan cheese and allow sauce to gently simmer for a further minute or so until the cheese melts and sauce thickens.
Add the salmon back into the pan, sprinkle with parsley and a squeeze of lemon juice. Taste test sauce and adjust salt and pepper, if needed.
Serve over pasta, rice or steamed veg.