Preheat the oven to 400 degrees F (200 degrees C).
Combine molasses, hot water, and baking soda together in a medium bowl; whisk in beaten egg until well combined. Pour mixture into deep dish pie shell.
Combine flour and brown sugar in a separate medium bowl; cut in shortening until mixture resembles coarse crumbs.
Sprinkle on top of pie filling.
Place pie on a cookie sheet and bake in the preheated oven for 15 minutes. Lower temperature to 350 degrees F (175 degrees C); bake for an additional 30 minutes.
