Do I need to cook the meat filling before stuffing ravioli? I been making ravioli this past week (3 types, butternut squash, various fungi, and spinach  for those interested).

Now I'm onto the meat. Its a pork, beef, and veal mixture.

My question is, do I need to cook the mixture before stuffing into the ravioli? If I do cook it, I'm worried the fat in the meat will make it so that everything won't stick together and therefore be harder to stuff.

On the other hand If I don't cook the meat, I'm worried the raviolis will have to cook too long for the filling to be cooked and the pasta will be way overcooked.

Which is the proper way?
Yes, cook the meat before stuffing into the ravioli.  If you are worried about your mixture being too fatty (which I didn't experience with a non-traditional beef and bacon ravioli), make sure to drain the meat well after cooking, perhaps patting it with clean paper towels to remove excess grease.