D.M.
I am an Occupational therapy assistant. I work in the school system and have had experience with children with sensory processing issues. As far as the actual eating goes just keep introducing and placing the item on her plate. If you can do not let her see the baby food jars. Tell her that she is getting bigger and big girls do not eat baby food, big girls eat there meals on plates(even if you are still giving her some baby foods). Another helpful thing is Social stories. One might read some thing like this.
Allison is a big girl she tries new foods when they are on her plate. This makes her Mommy very happy, then Mommy puts a sticker on the new food chart and I get a prize. There is a book on social stories. The author's last name is Gray. I'd bet you can find it on line. Good luck. D.