Preheat oven to 350°. In a small bowl, beat brown sugar, oil and egg until well blended. Beat in buttermilk. In a small bowl, combine flour, baking soda, ginger, salt and cinnamon; gradually beat into buttermilk mixture until blended. Stir in pears. Fill 18 paper-lined muffin cups two-thirds full. , For topping, combine brown sugar and ginger. Stir in butter until crumbly. Sprinkle over batter. , Bake 18-22 minutes or until a toothpick inserted in the center comes out clean. Cool 5 minutes before removing from pans to wire racks. Serve warm.