This version of the Crumble Apple Pie recipe was developed and became popular during World War II. Flour and sugar, among other food supplies were very limited. Women had to stretch these as much as possible to feed their kids and elderly family members. The recipe reduced flour and sugar by nearly 4/5 (!) of the original pre-war era apple pie recipes. 
The Apple Crumble Pie in a Skillet doesn’t have dough at the bottom and has a generous fruit to dough ratio. It requires no sugar to be added to apple filling, capitalizing on apple’s natural sweetness. This crumble pie recipe also doesn’t require any eggs, which makes it wallet-friendly and is suitable for people on a vegetarian diet….