Please note: Although there is no amount written by the spices, you can't really go wrong, so don't worry you won't over spice it.
For the stuffing: Break up the matzah into small pieces, put it in a bowl and pour boiling water over it. Let it sit to soften the matzah. Dice the onions and fry them in a 6 qt. pot. Slice the zucchinis thin, clean and slice the mushrooms and fry the vegetables with the onions. Add the salt, pepper, garlic and soy sauce to taste. Let the vegetables fry on med-low heat until they are soft. Mix the vegetables with the softened matzah.
Put a turkey sized oven bag (such as Reynolds) in a roasting pan. Put the turkey in the bag and stuff it with the matzah stuffing. Spice the turkey with all the remaining ingredients. Close the bag, cut a few holes in the bag and cover the pan with foil.
Bake in the oven at 275° F. overnight (for about 7-9 hours).