My dog attacked my other dog over food... PLEASE HELP!!!

The other day I was packing my dogs food in baggies to prepare for our weekend vacation. While measuring out the food, Molly (beagle/jack russel mix)came over to investigate and tried to get some food out of the food bin which is located on the bottom cabinet in the kitchen. She has always been a 'food hog' and will do anything for food. She has always been defensive around food. While she was trying to get in the food bin, our other dog Charlie (chihuahua) walked next to Molly to also see the food. This was the first time Charlie came this close to Molly when food was present. Molly turned around and literally attacked him. I freaked out and picked her up yelling "no molly". As I picked her up, she did not release and kept Charlie in her mouth. She had him by the neck. At his point, Charlie was now lifted off the floor crying very very loudly. My husband ran over and grabbed Charlie and tried to get him away from her. It took a few seconds before she released. I put her in the bathroom for 'time out' as we evaluated Charlie. He was extremly scared and cried when we tried to touch his neck. We realized that there was one puncture wound and he was bleeding. It was a little bit of blood but he had a small hole in his neck.
This was the first time she had done this and I didn't know what to do. She lunged at him 2 other times before when food was not present but we separated them and no one got hurt. This was the first actual 'dog fight'. It's very confusing because they are such BEST friends.
I am 16 weeks pregnant and I'm very afraid about this happening with the baby or another incident with Charlie.
Overall, Molly is a kind dog but does sometimes show aggression to other dogs but she has never attacked - she only shows teeth.
I REALLY want to help her. I can't bear to get rid of her. I love her and Charlie so much. Does anyone have any suggestions?

Thanks,
Becky :)

p.s. About the pregnancy thing... I always thought she would be good with kids a few young children/babies have been over and she's been fine. But now I am very worried.

I would do two things. First, keep them separate whenever you are handling food, and even feed them on opposite sides of the room. Second, I'd find a behaviorist in your area. This CAN be trained away, but you have to do so deliberately, consistently, and carefully.

And it is best to do so now, while the future baby is still safely inside. You want to get the training now, and keep reinforcing it, so when your baby is a toddler, the issue is well under control.

Hi Karen!! Thank you for your advice. I actually tried something new today during their dinner time and it worked really well. I had her stay next to her 'food area' and Charlie had to stay near his while I prepared the food. Normally, she would be next to the food bin while I was dividing up the food into their bowls. It actually took quite a few times for her to 'stay' near her area but it worked. I am trying to show her that I am the 'alpha dog' when it comes to food. I didn't give her the food until she listened and 'stayed'.

I am also going to contact a behavior specialist Tuesday morning.

Thank you,
Becky

p.s. I did use my one technique which seems good but PLEASE let me know if anyone else has suggestions for me.

i have 3 dogs 2 sister mastiffs and a spaniel they to get on very well but ive learnt that female dogs like to be dominant and will become very agressive over food , i to had a fight brake out with the 2 sisters which thankful was stopped but it couldve been very bad even though 1 needed vet treatment , i now feed them separate there never close and a gate is between them ,ive also got them use to a strict rule now noone touches anyone elses bowl , this has worked wonders :)