Heat oil in a large fry pan over medium heat, add onion, garlic, ginger, lemongrass and red pepper flakes, saute until onions are translucent.
Add pork, and fry until no longer pink, breaking it up as you go.
Add brown sugar and soy sauce and mix well.
Arrange pork in one layer in pan, increase heat to medium high, and let cook untouched until pork begins to caramelize - about 2-3 minutes.
Mix pork up, then again arrange in a single layer, and let cook untouched until more caramelization occurs - about 2-3 minutes. Repeat until pork is as caramelized and crunchy as you like.
Serve over rice or noodles with fresh vegatables of your choice.