Food-in-cheek Issues

Alot of kids go through a phase of storing things in their cheeks. I don't know why. But at 3, she should not be going to bed with food in her cheeks. She will get cavities.
You should let her feed herself. She's plenty old enough. You might have to have a little more patience with her during meal time and tell her, "Take a bite, chew, then swallow." You might even need to try telling her to open her mouth to show you nothing is in there before the next bite.
If she still has food in her mouth after a bite and won't swallow it, take her plate away from her and tell her she's done. Don't yell, don't punish her, just tell her that food is meant to make it to her tummy and if she's going to goof around about it, you'll try at the next meal. One bite, chew, swallow, then next bite. Don't put a time limit on it or anything, but limit how much she gets in her mouth. One bite at a time. If it's not swallowed, nothing else goes in. She's done.
And, no way is she going to bed with food in her cheeks. Make her use her toothbrush and spit all that out and brush and rinse before bed.
Let her feed herself and for now, forgo the idea that it's rude to open your mouth at the table with food in it. She needs to show you that she has swallowed before you let her take more bites.
Stuffing her mouth full isn't working so try the opposite. But let her use her spoon and fork herself.
Make it less of a battle and just be very matter of fact with her that she can't keep food in her mouth for a long time.
It's not good for her.
She won't starve.
Like I said, cut the yelling and all that.
If this has become a habit for her, it might take a few tries for her to get a new routine, but she can get it worked out.

Best wishes.

At 3 she can feed herself. I suggest that you put food on her plate or high chair tray and let her feed herself. Give her a specific amount of time to finish and then take the food away. I suggest giving her around 30 minutes to eat.

I suspect that eating has become a power struggle between the two of you. There are only 2 things that children can control and those are what and when food goes into their mouth and when and how it comes out at the other end. The reason for this suggestion is that you're continuing to try to get her to eat past an hour and you're screaming in frustration and she's crying in anger. You've told us that you've tried pleading and threatening. Eating should be a pleasure and not something that is forced upon us.

You need to let go of the need to be sure she eats. Let her be in charge. She will eat when she's hungry. It's great that she'll willingly eat almost anything. Now let her eat it on her own. She doesn't need for you to feed her. And she doesn't need to take long to eat it either.

What we eat is important for our health and so I think I understand why this is so important to you. Forcing her to eat just does not work.

She is looking for some control and independence, so I agree with the other moms that you need to let her feed herself and set a time limit or wait until everyone else in the family is finished. Then meal time is over. I agree that if she does not swallow, don't give her more. If she is vomiting, then either she does not like the food, or she is full. You are making meal times a very tense and anxious time for her and this is her way of telling you that she is unhappy about it. This can lead to eating disorders as she grows. Drs. will tell you that kids will eat when they are hungry, and many kids go through a phase where they will only eat white foods or eat a ton of the same food. My friend had to buy canned pineapple in bulk for about a year. Now her son is over pineapple and eats a variety of foods. You have to agree to give up some of your control. Take a deep breath, relax, and praise her when she does a good job.