About to toss a bunch of watermelon rinds into the trash? You can chop those leftovers up and turn them into a delicious Depression-era pie with a little culinary ingenuity, a dash of warming spices, and a batch of store-bought pastry. This led to the creation of inventive treats like the Depression-era water pie, which featured a filling made only of water, flour, sugar, vanilla, and butter. Watermelon pie (also known as watermelon harvest pie) was another imaginative recipe designed by farm wives who were reluctant to throw food scraps out. Some of the pink flesh attached to the outer skin was included to lend the filling a touch of summery sweetness.