1. Add the hot water, sugar and salt to a small bowl, stir until dissolved.
2. Stir in the beer and vinegar, add the shallots. Cover and refrigerate for one hour and up to 3 days.
3. In a small bowl stir together the chili sauce, brown sugar, and fish sauce, set aside.
4. Heat the oil in a large skillet over medium-high heat. Add the meatballs, pulling the pan back and forth until starting to sear.
5. Lower heat the medium, pour in the beer. Allow to simmer until most of the beer is gone, stirring occasionally.
6. Pour the sweet chili mixture over the meatballs, raising the heat slightly, adjusting to maintain a low boil.
7. Cook until the sauce has thickened and the meatballs are well coated.
8. In a small bowl stir together the sour cream and sriracha (can be done up to 3 days in advance).
9. Spread the sriracha sour cream inside the rolls, fill with meatballs, carrots, cilantro, pickled shallots and jalapenos.