-
1
Combine 1/2 cup water and white sugar together in a small microwave-safe bowl. Warm in the microwave to dissolve sugar, about 30 seconds. Add 2 tablespoons soy sauce, 2 tablespoons rice vinegar, ketchup, lemon juice, and sesame oil; mix until dipping sauce is well-blended. Cover with plastic wrap and chill, about 30 minutes.
-
2
Combine dry mustard with a few drops of water. Mix in remaining water until mixture is the consistency of hot mustard.
-
3
Whisk 2 tablespoons soy sauce, brown sugar, and 1/2 teaspoon rice vinegar in a small bowl to make stir-fry sauce.
-
4
Heat 2 tablespoons peanut oil in a wok or large skillet over high heat. Add pork; cook and stir until browned, about 5 minutes. Add remaining 1 tablespoon oil, water chestnuts, mushrooms, green onions, and garlic; saute until flavors combine, about 2 minutes. Pour in stir-fry sauce; stir to coat pork mixture evenly, 3 to 4 minutes.
-
5
Cut out lettuce stem and wash thoroughly. Discard outer leaf. Carefully peel off whole leaves and slice in half lengthwise. Arrange on a plate lined with paper towels.
-
6
Scoop dipping sauce into small bowls or ramekins. Mix in hot mustard and red chile paste to desired level of spiciness. Spoon pork filling into lettuce halves and roll up; top or dip wraps with dipping sauce.
