Marinate meat 4 to 6 hours. Roll and pat marinated meat pieces in butcher pepper until coarsley covered. In a 10" to 12" heated skillet and olive oil over high to medium high fire. Pan cear meat pieces until golden brown on all sides and remove from pan. Remove remaining particles from pan (do not wash pan). Add a touch more oil and shallots until golden over medium heat. Add sliced Portobellos, saute with shallots until shallots are carmelized. De glaze pan with brandy and reduce by half. Incorporate the demi glace and heavy cream, finish with whole butter, salt and pepper to taste. Simmer encrusted venison in sauce for 3 to 4 minutes (simmer longer for more well done) and serve. Garnish with some wild rice, rosemary, oven roasted potatoes or even some roasted root veggies.