Preheat broiler. Stick a skewer down center of pork fillets from thick end. Season with salt and pepper and wrap with strips of bacon. Brush with oil and broil about 8 minutes each side. To serve, slide from skewer and slice into medallions. Serve in sauce. Garnish with lemon and parsley.
Melt butter in saucepan over low heat. Add onion and cook until tender. Add mushroom stems and continue to cook. Mix in arrowroot and then white wine, hot water, and meat concentrate. Bring to a boil. Add sliced mushrooms, lemon juice, parsley and cayenne pepper at last moment.