In a small bowl, mix together mayonnaise, Sriracha, and green onion. Set aside.
To make the pickled vegetables:
In a medium sized bowl, combine carrots, cucumbers, salt and sugar. Let sit for about 10 minutes, drain liquid, and cover with rice wine vinegar. Let sit while you prepare the burgers.
To make the burgers:
In a medium sized bowl, mix together pork, fish sauce, sesame oil, garlic, green onion, Sriracha, and salt. Shape meat into small patties (about 8 sliders).
Heat sesame oil in a large cast iron pan over medium high heat. Add sliders and cook until pork is cooked through, about 8-10 minutes, flipping halfway though.
Cut buns in half, spread mayo, and add patty. Top with pickled vegetables, serrano pepper, and cilantro.
Recipe by Things I Made Today at https://www.thingsimadetoday.com/2015/11/06/bahn-mi-burgers/