Preheat oven to 375 degrees F. Spray a baking dish with cooking spray and set aside*.
Mix egg and buttermilk together in a shallow dish. Add the chicken and turn to coat.
Stir Panko, flour and some salt and pepper in a shallow dish.
Heat oil in large skillet over medium-high heat. Remove chicken from buttermilk mixture, allowing excess liquid to drop off, and dip into the Panko mixture, making sure each side is coated complete. Add to the skillet.
Cook for 2-3 minutes per side, or until golden brown.
Meanwhile, in a small sauce pan, combine Dijon, wine, honey and some salt and pepper. Let simmer for about 5 minutes. Add heavy cream and continue simmering.
Make a slurry with 1/2 tsp corn starch and 1 tablespoon of water. Then pour into saucepan and cook on low for 2 minutes. Remove sauce from heat and add sliced basil.
Transfer chicken to prepared baking dish and generously spoon sauce over each piece. Bake for 20 minutes, or until cooked through. Serve extra sauce on the side.
*Alternately, you could pan-fry in an oven-safe skillet and then transfer that to the oven, to save dirtying another dish.