Preheat your oven to 375°F (190°C).
Butterfly each chicken breast by slicing it horizontally but not completely through. Season both sides with garlic powder, paprika, Italian seasoning, salt, and pepper.
In a medium bowl, combine sundried tomatoes, spinach, mozzarella, Parmesan, cream cheese, and minced garlic. Mix well.
Spoon the filling into each pocket of the chicken breasts. Secure edges with toothpicks if necessary.
Heat olive oil in a skillet over medium heat. Sear the stuffed chicken for 2-3 minutes on each side until golden brown.
Transfer the skillet to the preheated oven and bake for 20-25 minutes or until the internal temperature reaches 165°F (74°C).