Preheat the oven to 375 degrees.
Place the chicken breasts on a cutting board and drizzle them with oil. In a small bowl, combine paprika, 1/2 teaspoon salt, garlic powder, and onion powder. Stir to mix, then evenly sprinkle the seasoning over both sides of the chicken.
Using a sharp knife, cut a pocket into the side of each chicken breast. Set the chicken aside.
In a small mixing bowl, combine the cream cheese, Parmesan, mayonnaise, spinach, garlic, red pepper flakes, and the remaining ½ teaspoon salt. Stir until well mixed.
Spoon the spinach mixture evenly into each chicken breast.
Place the stuffed chicken breasts in a 9×13 baking dish. Bake, uncovered, for 25-30 minutes or until the chicken is fully cooked through.