1. In a mixing bowl, combine ground pork, minced garlic, fish sauce, sugar, and black pepper. Mix well and form into 4 patties.
2. Grill the patties over medium heat for about 6-7 minutes per side, or until fully cooked.
3. In another bowl, mix rice vinegar, water, sugar, and salt. Add julienned carrots and daikon radish. Let it sit for at least 15 minutes.
4. In a small bowl, mix mayonnaise and sriracha to make the spicy mayo.
5. To assemble, spread spicy mayo on the buns, place the grilled patty, top with pickled vegetables, and garnish with cilantro.