If you need to find a recipe and only know some of the ingredients then try Super Cook:
http://www.supercook.com/
I grew up in S. California, Del Taco had a Taco Burger. Quite delicious. Basically taco filling on a bun instead of a tortilla. It's loose meat and you had to be careful of the meat falling out. I like to eat sloppy joes with a fork. I think eating one of them like a sandwich would be really messy. Arn't these type sandwiches basically a maid rite?