Follow these simple steps to create your delicious Gouda & Mushroom Stuffed Chicken:

1. Preheat Oven: Preheat your oven to 375°F (190°C).
2. Prepare Filling: In a skillet, heat 2 tablespoons of olive oil over medium heat. Add the chopped onion and garlic, sautéing until soft and fragrant.
3. Add Mushrooms: Add the finely chopped mushrooms to the skillet. Cook until the mushrooms release their moisture and become tender. Season with thyme, salt, and pepper.
4. Mix in Cheese: Remove the skillet from heat and stir in the shredded Gouda cheese until melted and well combined. Set aside to cool slightly.
5. Prepare Chicken: While the filling cools, place the chicken breasts between two pieces of plastic wrap or parchment paper. Gently pound them to an even thickness using a meat mallet or rolling pin.
6. Stuff Chicken: Take a portion of the mushroom and Gouda mixture and place it in the center of each chicken breast. Fold the chicken over to encase the filling, securing it with toothpicks if necessary.
7. Sear Chicken: In a large oven-safe skillet, heat the remaining tablespoon of olive oil over medium-high heat. Sear the stuffed chicken breasts for 3-4 minutes on each side until golden brown.
8. Bake: Transfer the skillet to the preheated oven. Bake for 25-30 minutes or until the chicken is cooked through and the juices run clear.
9. Optional Crunch: If desired, sprinkle breadcrumbs on top of the chicken during the last 5 minutes of baking for a crunchy topping.
10. Rest and Serve: Allow the chicken to rest for a few minutes before serving. Remove toothpicks if used.