Preheat your oven to 375°F (190°C).

In a mixing bowl, combine diced pears, crumbled Gorgonzola cheese, chopped spinach, and minced garlic. Season with salt and pepper.

Carefully slice each chicken breast on one side to create a pocket for the filling. Fill each breast with the pear mixture.

If the openings are wide, secure them with toothpicks to prevent leaking.

In an oven-safe skillet, heat a tablespoon of olive oil over medium-high heat, then sear the stuffed chicken breasts for about 4-5 minutes on each side.

Transfer the skillet to the oven and bake for 20-25 minutes until the internal temperature reaches 165°F (75°C).

Once baked, let the chicken rest for a few minutes, then slice and serve with balsamic vinegar if desired.