Slice pork tenderloin into ¼ inch thick rounds. To make this easier you can place the meat in the freezer for 15 minutes before slicing.
Soak bamboo skewers if using or skip this step if you prefer metal skewers.
In a food processor or blender, blend together the oil, soy sauce, fish sauce, lime juice, garlic, lemongrass, ginger, brown sugar and pepper until a loose paste is formed.
In a bowl mix the marinade with the sliced pork and thread the pork through the top and bottom of the meat, about 4 to 5 pieces per skewer placed on a sheet pan and let marinade 1 to 2 hours.
Preheat the grill over medium high 400°F and grill pork skewers about 3 to 4 minutes per side.
Noodle Salad
While the pork is marinating, in a small bowl add the carrots, rice vinegar and set and set aside to quick pickle.
Cook vermicelli noodles to package instructions and immediately strain and cool with cold water. Set aside and drizzle with a teaspoon of neutral oil to keep from sticking and place in the fridge.
In a small bowl whisk together the sugar, water, fish sauce, lime juice, garlic and chili and place in the fridge until ready to toss.
Assemble the noodles with the dressing and toss. Add the carrots, peanuts, herbs and sprouts and serve with skewers and cut limes.