Preheat the oven to 375°F (190°C). Set a rack in the center.

Use a sharp knife to cut a pocket into each chicken breast without slicing all the way through.

In a bowl, combine ricotta, lightly mashed blackberries, Parmesan, garlic powder, salt, and pepper. Mix until smooth.

Spoon the ricotta mixture into each pocket. Secure with toothpicks if needed.

Heat olive oil and butter in an oven-safe skillet over medium heat. Add the breasts and sear for 3–4 minutes per side until golden brown.

Transfer the skillet to the oven and bake for 18–20 minutes, or until the chicken reaches 165°F and juices run clear.

To make the glaze, combine balsamic vinegar, honey, and chicken broth in a small saucepan. Bring to a simmer and cook for 4–5 minutes until slightly thickened.

Stir in fresh thyme and adjust seasoning if necessary.

Remove chicken from oven, let rest for 3 minutes, then drizzle the glaze over each breast.