Preheat oven to 375 degrees then line a half sheet pan with foil and spray with nonstick spray. Set aside.
Using a sharp knife, cut a pocket horizontally into each chicken breast then set aside.
In a small mixing bowl, add apples, shredded cheese, lemon juice, 1/2 teaspoon dried thyme, dried oregano, salt, and pepper then stir to combine and stuff 1/4 of the mixture into each chicken breast pocket. Close with toothpicks if desired.
Heat extra virgin olive oil in a large skillet over medium-high heat. Combine flour, salt, and pepper in a shallow dish then dredge chicken breasts in mixture, tapping excess flour off. Place chicken into skillet then saute until golden brown on one side, 4-5 minutes. Flip then saute until other side is golden brown, 3-4 minutes and then transfer chicken to preparedbaking sheet and place into the oven to finish cooking through, 5-7 minutes.
Meanwhile, add chicken broth, apple juice, dijon mustard, apple cider vinegar, and a pinch of dried thyme to skillet then increase heat to high. Cook until sauce has reduced, about 5 minutes, then taste and add salt and pepper if necessary. Plate chicken then drizzle with pan sauce.