Preheat your oven to 375°F (190°C).
Lay the salmon fillets skin-side down on a clean surface.
In a bowl, mix together chopped spinach, feta cheese, cream cheese, garlic, lemon juice, salt, and pepper until well combined.
Spread the spinach mixture evenly over each salmon fillet.
Carefully roll the fillets from one end to the other, creating pinwheels.
Secure each pinwheel with toothpicks if necessary.
Place the pinwheels in a greased baking dish.
Drizzle olive oil over the top for added flavor.
Bake in the preheated oven for 15-20 minutes, or until the salmon is cooked through.
Remove from the oven, garnish with fresh herbs, and serve.