Mix water, vinegar, olive oil, tomato paste, brown sugar, black pepper, salt, oregano, cumin, paprika, and hot sauce in a bowl. Let it sit for at least a day for enhanced flavor.
In a medium bowl, mix ground beef with dry ingredients (salt, onion powder, garlic powder, oregano, cumin, black pepper, and paprika).
Finely chop half of the onions and garlic and add them to the beef mixture. Chop the remaining onions coarser.
Remove casing from chorizo links and break them down. Mix chorizo thoroughly with the beef mixture.
Remove casing from chorizo links and break them down. Mix chorizo thoroughly with the beef mixture.
Add ketchup to the mixture if needed for moisture.
Form the mixture into 4-5 ounce meatballs and refrigerate for at least 30 minutes.
If using a skillet, flatten the meatballs into thin patties. Cook for 3 minutes on one side, then flip.
Add coarsely chopped onions and cover with the prepared sauce after flipping. Cook for an additional 3 minutes.
Serve on toasted Cuban rolls or hamburger buns. Top with additional chopped onion, a pile of julienne fries, and ketchup.