butternut & corned beef hand pies

The combination sounds a bit off to me, but the sweet-salty pairing might work. If I were doing it, I would use ham or Italian sausage in place of the corned beef, and add a bit of fennel, rosemary, and or sage.

I think this could work if you can balance out the sweetness from the butternut squash and the corned beef (I find corned beef to be on the sweeter side). Maybe instead of the aforementioned seasonings which are excellent additions to squash go in a different direction. Dry mustard? It'll give the dish a kick.

Also, I would dice the butternut squash and deeply carmelize it in a pan prior to stuffing in the handpies otherwise you'll be stuck with a mashed mess with chunks of corned beef sticking out.