• Step 1: Preheat your oven to 400°F (200°C). Grease a baking dish or line it with parchment paper.
• Step 2: In a large skillet, heat the olive oil over medium heat. Add the minced garlic and diced onion, and sauté for 2-3 minutes until fragrant and translucent.
• Step 3: Add the chopped spinach to the skillet and cook, stirring occasionally, until the spinach is wilted, about 2-3 minutes. Remove the skillet from heat and set aside.
• Step 4: In a small saucepan, combine the heavy cream, Parmesan cheese, dried basil, salt, and black pepper. Whisk the mixture and heat it over medium heat, stirring occasionally, until the cheese has melted and the sauce is smooth, about 5 minutes.
• Step 5: Place the salmon fillets in the prepared baking dish. Spoon the spinach mixture evenly over the top of the salmon, then pour the creamy Parmesan sauce over the entire dish.
• Step 6: Bake the Salmon Florentine in the preheated oven for 15-20 minutes, or until the salmon is cooked through and flakes easily with a fork.