Hello,

Your dog is simply guarding a precious
treasure. Since you are the boss,
she should not be growling or snipping
at you period.
I teach my dogs when they are pups, that
I can take anything away from themI want.
(safer to do when they are puppy's than
big mature dogs) lol
I also taught them the command "Give"
which is helful.
You might try giving her a chew treat, and when you go near her and she begins to growl,
I would sharply repremand her, and not let her have the treat till she stops growling. If you are afraid she might bite you, where gloves.
You might even want to start doing a little hand feeding. (could be messy)
Put your hand in her food bowl and
put some food in it,
Make her eat from your hand. Keep this up
for 3-4 weeks.
After your dog no longer growls,
periodically keep this up, or she
might regress. I am sure you will get
some great advice from others on this topic.