To make the pickled vegetables put the vinegar, water, sugar, garlic, and salt in a medium saucepan.

Bring the mixture to a boil over medium high heat. Add in the carrots, cabbage, and red onions and boil, stirring frequently, for 3 minutes.

Remove from heat and let cool.

In a large skillet heat the beef over medium heat. Cook for 5 minutes, breaking up the pieces, until it's cooked through.

Add in the garlic, ketchup, hoisin, water, soy sauce, rice wine vinegar, and sriracha and stir together.

Continue cooking for 5 minutes or until the sauce begins to evaporate and the mixture because thicker and saucy.

Put the mixture on the buns and top with the pickled vegetables.