I personally really dont like using food as a bribe for training. IMO the horse sees you as the dinner bucket. If this horse has fear issues, she needs to see you as safety and comfort. If she is in a paddock by herself, you could try some exercises that will encourage her to want to be with you.
I go into the paddock with the halter and either a long lead (about 12')that I can use to push the horse or a lunge whip. I am looking for the horse to look at me with both eyes. If they give me one eye or turn away, I pop the whip and push them. I aggressivly follow them. At some point they will turn to look and see what you are doing. The instant I get two eyes, I immediatly stop moving and relax my posture. I wait a few seconds to see if they are going to stay. If they turn or give me one eye I repeat the above process.
If they stay and continue to look at me, I walk towards them in a zig zag pattern, not directly at them. If at any point they turn, I push as above until they again stop and look at me. You want to watch them to see their movement, but do not look them directly in the eye when you are coming up to the horse.
When I get to where I am next to the horse, I rub them starting at the neck/whither junction and work my way up to the head. If the horse has head shy problems, you will start to see it the closer you get to the head. Do approach and retreat on the rubbing until you can put the halter on.
If you will do this each time you go to get her, she will start to understand that when you come for her, she will work if she runs or disrespects. Pushing her is what another dominant horse would do, it established your role as the leader. When she sees you as her leader, she will see you as safety and comfort and will want to be with you. That is when you get the horse catching you