In a large saucepan, bring pears, the 1/3 cup brown sugar, 2 tablespoons water, and lemon juice to boiling, stirring to dissolve sugar. Reduce heat. Cover and simmer for 5 minutes or until fruit is almost tender, stirring occasionally. Combine 2 tablespoons water and the cornstarch; add to pear mixture. Cook and stir until thickened and bubbly.
Meanwhile, for biscuit topping, in a mixing bowl stir together the flour, crushed graham crackers, pecans, the 1 tablespoon brown sugar, and baking powder. Cut in the margarine or butter until the mixture resembles coarse crumbs. In another mixing bowl combine egg white and milk. Add all at once to the flour mixture, stirring just until moistened.
Spoon the hot fruit mixture into a 2-quart square baking dish. Immediately spoon the biscuit topping into 6 mounds atop the hot fruit mixture. Combine the sugar and cinnamon. Sprinkle sugar-cinnamon mixture over the biscuit mounds.
Bake in a 400 degree F oven for 12 to 15 minutes or until a wooden toothpick inserted in the center of a biscuit comes out clean. Serve warm. If desired, serve with half-and-half, light cream, or ice cream. Serves 6.