Preheat the oven to 375°F (190°C).

In a medium bowl, combine the Brie, cranberries, spinach, and rosemary. Stir until well mixed.

Butterfly each chicken breast by cutting it horizontally, enough to create a pocket without cutting all the way through.

Season the inside and outside of the chicken breasts with salt and pepper.

Fill each chicken breast with the cranberry Brie mixture, using toothpicks to secure the opening if necessary.

Heat olive oil in a large skillet over medium-high heat. Sear the chicken breasts for 4-5 minutes on each side until golden brown.

Transfer the seared chicken to a baking dish and pour chicken broth around the breasts.

Bake in the preheated oven for 20-25 minutes, or until the chicken is cooked through.

Let the chicken rest for 5 minutes before serving.