It is made just like a regular pie, except bigger and better.
Slab pies are made in a rimmed baking sheet (also called a jelly roll pan) so they are slightly shallower than standard pies and can feed more people.
The result is a slice with a truly spiritual ratio of crust to filling.
Here are some recipes to get your started down the road to enlightenment:
Get the recipe. Taro root looks like a potato, basically, and cooks the same way but has a more interesting nutty flavor. You can find it at specialty grocery stores and probably also at Asian grocery stores.
Get the recipe. (Same recipe as the first image in this post.)
Read more: http://buzzfeed.com/emofly/slab-pies