1. Cut the garlic and onion into small pieces.
2. Heat the oil in a large skillet over medium-high heat. Season the salmon fillets on both sides with salt and pepper and sear in the hot skillet, flesh side down first, for 5 minutes on each side, or until cooked to your liking. Once the salmon fillets are cooked, remove them from the skillet and set aside.
3. In the same skillet, melt the butter in the remaining cooking juices. Add the garlic and fry until fragrant (about one minute). Add the onion and sauté until translucent.
4. Add the sun-dried tomatoes and fry for 1 to 2 minutes to release their flavors. Finally, pour in the vegetable broth and let the sauce reduce slightly.
Reduce the heat to low, add the heavy cream and bring to a gentle simmer, stirring occasionally.
5. Season the cream sauce with salt and pepper to taste.
Add the spinach leaves and let them wilt in the sauce, then add the Parmesan cheese. Simmer the cream sauce for an additional minute until the cheese is melted.
6. Return the grilled salmon fillets to the skillet; sprinkle with parsley and spoon the sauce over each fillet. Serve the creamy garlic Tuscan salmon over steamed vegetables, cauliflower rice, or pasta!