pasties and patties
 

Hi
I wish to try different fillings in pasties.
Sometimes you cook/brown the meat before filling the pastry (patties for
instance), sometimes you don't.
Are there any rules of thumb as to when the meat needs to be precooked and
when/how the veg goes in.
I'm thinking of starting with spicy chicken and some potatoes. But would
like to swap meats according to what's available.
Obviously I don't wish to eat raw meat! But does over cooking matter given
that it's in pasty form. i.e can it all be precooked then used to fill the
pastry?
Cheers me Dears.
BB