Well, I'm not sure how old your pup is but if she knows what NO means you may want to use it. When we teach any of our dogs or puppies to take a treat we always start with patience. We have always taught our dogs to sit, stay, and then slowly while saying "be nice" brought the treat to their mouth, then tell them it is OK to take it. BUT, if they jump or try to grab we pull back and say NO. It can be tricky and sometimes takes two people at first, one to hold the pup back. We have started teaching our dogs to sit, stay, and wait till we say OK before they eat anything, when some one tried to poison one of our dogs. None of our dogs now, will take food unless they are told it is OK. Besides, it is much easier to feed them when they are not jumping all over the place trying to get at the food. And it stopped them from trying to grab food from our kids when the kids were little.
Just be patient, dogs can learn very quickly when food is involved.
Good luck