Preheat oven to 375
Roll out pie dough onto a lightly floured surface into a circle(ish) that thin, but to to thin (maybe a little thinner then a 1/2 inch) and stick on a baking sheet and in the fridge to chill while doing the other stuff.
Now slice apple, onion, and the neck of the squash into 1/4 inch thin slices.
Grab you dough from fridge, layer the squash on the dough, leaving about an inch of a boarder, then the apple slices, and lastly the onion. Fold sides of dough over the heap if stuff, tucking and folding to make a nice little package. Drizzle the top and the sides with a little bit of olive oil and sprinkle with a dash of salt.
Stick into preheated oven for about 45 minutes, or until the crust is nice and flakey golden brown and the stuff in the middle is soft and tender.
Remove and let cool for a few minutes and tuck on in!