01 -
Butterfly each chicken breast by slicing horizontally to open like a book, keeping one side attached.
02 -
Sprinkle inside of each chicken breast with kosher salt, black pepper, and thyme.
03 -
Layer spinach or arugula on one side of each chicken breast. Top with 3 slices each of green apple and brie cheese.
04 -
Fold chicken breasts over to encase the filling and secure with toothpicks if desired.
05 -
Combine Dijon mustard and coarse ground mustard in a small bowl. Brush half the mixture onto the tops of the chicken breasts.
06 -
Heat olive oil in a large skillet over medium-high heat. Place chicken in skillet mustard side down. Brush remaining mustard onto the other side. Sear 3-4 minutes per side until golden brown.
07 -
Cover skillet, reduce heat just below medium, and cook for 5-8 minutes until chicken is cooked through.
08 -
Transfer chicken to plates, drizzle with pan juices or sauce, and serve immediately.