Slice the beef into strips about half an inch thick and marinate them in soy sauce and vinegar for about one hour.
Once the meat is marinated, heat up a pan and fry the meat is golden brown then set it aside.
Boil the beef or chicken liver and fry it like the beef strips. Once its fried, slice the liver into medium-sized cubes and set it aside.
Heat up 1 tablespoon of oil in a wok or heavy skillet, then saute garlic and onion, chili, and bell pepper.
Pour about 1/2 cup of the soy sauce and vinegar mixture from the beef marinade.
Simmer the mixture for a few minutes then add the pepper, beef broth cube, and season with salt. Make sure to stir them in to incorporate the flavors.
When the mixture is simmering, pour it on the fried beef strips and liver.
Add the mayonnaise and some lemon juice then mix until all the ingredients are well coated.
Transfer the mixture to a heated metal plate and serve it hot