Heat 1 tbsp of extra virgin olive oil in a large oven-safe skillet over medium-high heat. Add 8 ounces of thinly sliced cremini mushrooms in an even layer. Let sear undisturbed for 7 minutes to build color before stirring. Continue cooking 3-4 minutes until softened and browned.

Turn the heat to low. Stir in 4 minced garlic cloves, 0.5 teaspoons of dried oregano, and 1 teaspoon of fresh thyme leaves. Cook for 45 seconds until fragrant, then stir in the lemon zest. Season with a pinch of salt and black pepper, then transfer the mushroom mixture to a plate to cool slightly.

Slice a deep horizontal pocket into the thickest side of each of the 4 chicken breasts, being careful not to cut all the way through. Rub the exterior and interior pockets evenly with 0.5 teaspoons of garlic powder, 0.5 teaspoons of smoked paprika, and the remaining salt and freshly cracked black pepper.

Place one slice of cold Swiss cheese inside each pocket, then spoon in the cooled mushroom filling. Fold the chicken back over the filling and secure the edges with 2-3 wooden toothpicks. Drizzle a little of the fresh lemon juice over the outside of each breast.

Preheat your oven to 375°F (190°C). Wipe out the skillet, add the remaining 2 tablespoons of extra virgin olive oil, and heat over medium-high heat. Sear the stuffed chicken for 8 minutes per side until deep golden-brown.

Transfer the skillet directly to the oven. Bake for 18 minutes, until a meat thermometer in the thickest part reads 165°F (74°C). In the last 2 minutes, you can lay a little extra Swiss and a few reserved mushroom slices on top for that bubbly, golden finish.

Let the chicken rest for 5 minutes so the juices redistribute. Remove the toothpicks, garnish with 2 tablespoons of chopped fresh flat-leaf parsley, and spoon the savory pan juices over the top. Serve with lemon wedges on the side.