I haven't used this for a hangover, but it is my sick tummy favorite soup, sort of based on a Chickasaw recipe:
1 lb ground meat (pork's best)
2 regular sized cans of hominy, and their liquid
1/2 bag frozen bird's eye pepper stir fry vegetables (this is the one with just bell peppers and onions)
3 cans chicken broth
ground black pepper
Paprika
(you use 2 or three times more paprika than black pepper, probably at least half a teaspoon.)
Fry and drain the meat, add the peppers, and when they are about done, add broth, hominy and liquid, and spices.
I have made it with hominy grits when I didn't have the canned hominy.
Simple soup, very easy on a sicky tummy, and probably very nice on a bad hangover. Haven't had one of those since about 1990. Never ever ever intend to get that sick again by my own hand!
Forget the hangover cure... That just sound tastey all on it's own.