Streusel topping: Combine brown sugar and flour; cut in the butter until crumbly. Stir in chopped pecans. Set aside.
Bake sweet potatoes @ 350 until soft. Remove and cool. Using a fork poke holes in pie shell to prevent bubbles, Pre bake pie shell for 5 minutes. Meanwhile, Peel skin and thoroughly mash potatoes. Make them as smooth as possible. Add zest, juice and molasses. Mix thoroughly. Separate eggs. Whip egg whites until stiff peaks form. Fold egg yolks and milk into potato mixture, gently add egg whites and fold until just incorporated, do not over mix. Place mixture into pie shell, gently sprinkle streusel topping over mix and bake for 30- 40 minutes. Remove and serve immediately.
Nancy and Tim Bass - Sunburst Tomato