Place a large skillet over high heat to preheat. Pat dry top an bottom of each steak, then lightly rub with the canola oil. Season both sides of each steak heavily with the kosher salt.
Sear the steaks in the hot pan for 3 minutes per side, then remove to a serving platter and cover loosely with foil. Lower heat to medium and melt the butter in the same pan. Add the mushrooms and saute, stirring only occasionally, until lightly caramelized. Add the garlic and saute until fragrant. Deglaze the pan with cognac and beef stock, then simmer until liquids have reduced to almost nothing. Remove the pan from the heat and fold in the chilled Camembert cubes. Divide mixture between the steaks, garnish lightly with minced parsley, and serve immediately.