Pork and Mango Rolls

Name: Pork and Mango Rolls
Ingredients: 1/2 cup fish sauce; 1/4 cup canola oil; 1/4 cup rice-wine vinegar; 1 stalk lemon grass, crushed; 2 cloves garlic, finely sliced; 1/2 inch piece ginger, finely sliced; 1 green chile pepper, finely sliced; 2 teaspoons freshly ground black pepper; 1 pork tenderloin (about 1 pound), silver skin trimmed; 6 eight-and-a-half-inch rice-paper wrappers; 1 bunch watercress, washed; 1/2 mango, peeled and cut in matchsticks; 1/2 small jicama, peeled and cut in matchsticks; 1 cup fresh basil leaves, washed and dried