Preheat oven to 350˚F. Butter the inside of an 8 or 9 inch cast iron skillet.
Cream butter and sugar.
Beat eggs, vanilla and grated orange peel until light and fluffy.
In separate bowl, mix flour, baking powder, baking soda, salt and ginger.
Mix dry ingredients with creamed mixture. Beat till just blended. Batter will be very stiff. Add chopped pears to batter. Mix well and spoon into skillet. Spread evenly and top with sliced Bosc pears and pecans. Bake at 350˚F for 35 minutes. Serve warm with ice cream.