01 -
Set the oven temperature to 190°C (375°F) to prepare for roasting.
02 -
Butterfly each chicken breast horizontally without cutting through completely, opening them like a book.
03 -
Season the chicken interiors with salt and black pepper, then layer 2 slices of prosciutto, apple slices, and 2 sage leaves on each breast.
04 -
Fold the breasts closed. Heat 2 tablespoons of butter and olive oil in an oven-safe skillet over medium-high heat. Brown the chicken for 3–4 minutes per side until golden.
05 -
Transfer the skillet to the oven and roast for 15–20 minutes until fully cooked.
06 -
Remove chicken from oven, place on a plate, and tent with foil to retain heat.
07 -
Return skillet to medium heat. Deglaze with apple cider, scraping browned bits. Whisk in Dijon mustard, apple cider vinegar, and the remaining butter until smooth.
08 -
Let sauce reduce and thicken for about 5 minutes. Season with salt and black pepper to taste.
09 -
Return chicken to skillet to rewarm, spoon sauce over breasts, then plate and garnish with chopped parsley.