Suggest Remedy For Stretched Meal Time

My three year old daughter is not a picky eater at all. The problem is that she takes forever to eat. About 2 hours to eat half a sandwich. She does not snack between meals, so I know she's hungry. I've watched her and I think the reason why she is so slow is she chews one small bite of food for a very long time. I mean at least 5 minutes for one little bite. She doesn't seem to have any problems swallowing so I'm not sure what the problem is. It is gotten beyond frustrating. We have tried the timer, taking away privileges, just leaving her to eat on her own but nothing seems to matter to her. We do not have 6 hours a day to dedicate to her eating her meals. Any suggestions for frustrated parents.