Lettuce Wraps

I've tried some other recipes that claim to be PF Chang lettuce wraps, but none of them have come as close as this one.

Lettuce Wraps
Condiments:
1 T hot mustard
1 tsp red chili paste

Sauce:
1/4 C water (boiling)
1/4 tsp sugar
2 tbsp rice vinegar
2 tbsp ketchup
2 tbsp soy sauce
1 tbsp lime juice
1/4 tsp sesame oil
1/2 tsp ginger (grated)

Stir Fry:
3 tbsp canola oil
4 chicken breasts (skinless, boneless)
1 C water chestnuts (5 oz dry weight tin, diced)
1/2 C straw mushrooms (diced)
1/3 C green onions (diced)
2 tsp garlic, (minced)
3 tbsp soy sauce
3 tbsp brown sugar
1 tsp rice vinegar
1 C rice noodles (optional)
10 iceberg lettuce leaves

Place condiments in separate serving dish. Combine sauce ingredients well, then set aside. Stir fry chicken in oil, 4 minutes each side. Remove. Chop chicken into dime-size pieces, return to pan along with remaining ingredients (which I dice pretty finely in a chopper) and stir fry until heated through. Spoon into lettuce cups and drizzle with sauce. Hot mustard and red chili paste can be added to the sauce according to taste.