1. Preheat your oven to 375°F (190°C). Line a baking dish with parchment paper or lightly grease it with olive oil.
2. Prepare the mushroom filling: In a medium skillet, heat 2 tablespoons of olive oil over medium heat. Add the shallots and garlic, sautéing until fragrant and translucent, about 2 minutes.
3. Add the chopped mushrooms and thyme to the skillet. Cook, stirring occasionally, until the mushrooms have released their moisture and are browned, about 8-10 minutes. Season with salt and pepper. If using, pour in the white wine or chicken broth and cook until the liquid evaporates, about 3 minutes. Remove from heat and let cool slightly.
4. Using a sharp knife, create pockets in each chicken breast by slicing horizontally through the thickest part, being careful not to cut all the way through.
5. Stuff each chicken breast with a generous amount of the mushroom mixture and shredded Gouda cheese. Secure with toothpicks if needed to keep the filling inside.
6. Heat a drizzle of olive oil in a large oven-safe skillet over medium-high heat. Sear the stuffed chicken breasts for 3-4 minutes on each side, until golden brown. This step locks in the juices and adds a beautiful crust.
7. Transfer the skillet to the preheated oven (or move the chicken breasts to your prepared baking dish) and bake for 15-20 minutes, or until the chicken reaches an internal temperature of 165°F (74°C).
8. Remove from the oven and let rest for 5 minutes before slicing. Garnish with fresh parsley and serve warm.

I remember the first time I made something similar with Nonna Rosa—it was a bit intimidating to stuff the chicken perfectly, but she reminded me that cooking is about love and patience, not perfection. That advice has stuck with me through every kitchen adventure, especially when Olivia and Isabella help me stuff the chicken, their tiny hands enthusiastically working alongside mine.