Start by heating olive oil in a skillet over medium heat. Add garlic and sauté until fragrant, then toss in the chopped spinach and cook until wilted. Remove from heat and mix with cream cheese, Parmesan, lemon zest, and seasoning until smooth and creamy.
Using a sharp knife, carefully cut a pocket into the side of each salmon fillet. Be gentle to avoid cutting all the way through. Season the outside of the salmon with salt, pepper, and paprika for added flavor.
Spoon the spinach mixture into each fillet pocket generously. Press gently to secure the filling, and use toothpicks if needed to keep everything intact while cooking.
Place the stuffed salmon fillets in a preheated oven at 375°F (190°C). Bake for about 15–20 minutes, or until the salmon is fully cooked and flakes easily with a fork.
Once cooked, remove from the oven and drizzle with fresh lemon juice. Let the salmon rest for a couple of minutes before serving to lock in the juices and flavors.