This is a completely unconventional way that has been very controversial when I've mentioned it before. But the way I broke out of a lot of my food aversion issues is watching videos of how people eat around the world and seeing that things outside of my safe foods are not going to hurt me. In doing that since I was in my early teens I have got to the point I fairly regularly eat raw or rare meats including the "usda no no foods" such as poultry, pork, and organ meats. I also eat vegetables that i had previously had an issue with due to appearance. Obviously this has taken me a very long time (5+ yrs) to get to this point but it's definitely possible.