Preheat oven to 350F (175C). Line the bottom of an 8 x 8-inch baking pan with a sheet of parchement paper. Mix together the graham cracker crumbs, melted butter and 1/4 cup brown sugar in a large bowl until crumbs are thoroughly moistened. Place into an even layer of crumb mixture in bottom of prepared baking pan. Freeze for 30 minutes. Whip the cream cheese into a mixing bowl and beat until whipped with sugar. Add the pumpkin and beat until creamy. Add eggs and beat until thoroughly combined. Pour pumpkin cream cheese mixture evenly over graham cracker crust. Bake for 35 - 40 minutes or until a knife inserted in center of the pumpkin cream cheese comes out clean. Remove from oven and cool to room temperature. Cover with plastic wrap and chill for 3 hours or overnight. Cut into 1 /12 x 1 1/2-inch bars and top with whipped cream, if you like, before serving. Store in an airtight container in the refrigerator.