Instructions:

1. Preheat & Prep:
   Preheat your oven to 400°F (200°C). Lightly grease a baking dish and set aside.

2. Cook the Filling:
   Heat olive oil in a skillet over medium heat. Add chopped mushrooms and sauté for 4-5 minutes until soft and golden. Stir in the minced garlic and cook for another 30 seconds.

3. Add Spinach:
   Toss in the fresh spinach and cook until wilted (about 2 minutes). If using frozen spinach, just stir it in and heat through. Season with a pinch of salt and pepper. Remove from heat and let cool slightly.

4. Make it Creamy:
   In a bowl, mix the cooked mushroom-spinach mixture with cream cheese, mozzarella, and parmesan until creamy and well combined.

5. Prepare the Chicken:
   Using a sharp knife, cut a deep pocket into the side of each chicken breast, being careful not to cut all the way through. Season the outside of each breast with salt, pepper, paprika, and Italian herbs.

6. Stuff the Chicken:
   Spoon the creamy filling evenly into each chicken pocket. Secure with toothpicks or kitchen twine to keep everything sealed.

7. Sear (Optional):
   For extra flavor, sear each stuffed breast in a hot skillet with a little oil for 2-3 minutes per side until golden.

8. Bake:
   Transfer the chicken to your prepared dish. Cover with foil and bake for 20 minutes, then uncover and bake an additional 10-15 minutes, until the chicken is cooked through (165°F/74°C internal temperature).

9. Serve:
   Let rest for 5 minutes. Remove toothpicks, slice, and serve with your favorite sides. Enjoy!