canned or jarred turkey gravy and sliced turkey (either from the deli or home-cooked and then sliced up). add water to thin the gravy out a bit if you want...
to spice up the gravy add in salt/pepper
to taste, a bay leaf, some garlic powder and some onion powder (or even slice up an onion and put it in).
you could also put in some thyme and some sage - or even the 'poultry mix' - it has thyme, sage, garlic, onion, etc in it.
for extra added flavor put in a cup or two of white wine...the alcohol will cook away leaving you with a really nicely flavored gravy.