Meanwhile, place the chicken breast in a large plastic zipper-top bag. Pour in remaining sauce and turn in bag until evenly coated. Refrigerate 30 minutes or overnight.
Preheat oven to 400 degrees. In a large oven-proof skillet over medium-high heat, heat butter until the foaming.
Add mushrooms and sauté until they have released most of their liquid and have started to turn brown, about 5 to 7 minutes. Transfer to a bowl and wipe out skillet.
To the same skillet, heat oil until shimmering. Add chicken (discarding any remaining marinade) in a single layer and do not move until a golden-brown crust forms, about 5 minutes.
Flip each piece and continue to cook until the second side is browned, about 5 minutes longer.
Remove from oven and garnish with parsley if desired. Serve with reserved sauce on the side for dipping.
Adapted from Top Secret Restaurant Recipes.