General Tso's Chicken

This was fantastic!  There are a few specialty ingredients, but they were all pretty cheap (and enough to make many, many batches of this).  I wasn't sure how the cornstarch battering was going to work out, but it was so easy and perfect.  Adapted slightly from The Chinese Takeout Cookbook.

Serves 4.

Marinade:
1 Tbsp soy sauce
1 Tbsp Chinese rice wine or dry sherry (I used regular white wine)
2 large egg whites

1 lb. boneless, skinless chicken thighs, cut into 1-inch cubes

1 tsp white sesame seeds (optional)

Sauce:
1/4 c chicken stock or water
1 1/2 Tbsp tomato paste
1 Tbsp soy sauce
1 Tbsp white rice vinegar (I used regular)
1 tsp hoisin sauce (from the asian aisle)
1 tsp chili sauce (I used sriracha)
1 tsp sesame oil (I used canola)
1 Tbsp sugar
1 tsp cornstarch

1 1/2 cups cornstarch
salt and pepper
3 cups oil for frying (I doubt I used this much)
8 dried whole red chilies, or 1/4 tsp crushed red pepper flakes (I used the flakes; omit for the spice-sensitive)
2 cloves garlic, minced
Scallions or green onions, for garnish

1. Marinate the chicken: In a large bowl, combine soy sauce, wine, and egg whites.  Add the chicken and stir gently to coat.  Let stand at room temperature for 10 minutes.
2. (If using sesame seeds) In a small pan, toast the sesame seeds for about 1 minute, until they become lightly brown and aromatic.  Transfer to a dish and set aside.
3. Prepare the sauce: In a small bowl, combine the chicken stock, tomato paste, soy sauce, vinegar, hoisin sauce, chili sauce, oil, sugar, and cornstarch.  Stir until the sugar and cornstarch are dissolved.  Set aside.
4. Toss the 1 1/2 cups cornstarch with salt and pepper (about 1/2 tsp each) in a large bowl or deep plate.  Coat the marinated chicken in the cornstarch mixture and shake off any excess before frying (Note: You should have the oil heated before coating the chicken, or the cornstarch coating gets pasty.  I don't know if this affects the finished product, but it doesn't seem ideal).
5. Heat the frying oil in a wok or heavy-bottomed pot until it registers 350 on an instant-read thermometer.  Working in 2 or 3 batches, add the first batch of chicken cubes and deep-fry until lightly golden on the outside and cooked through, 3-4 minutes.  Remove the chicken with a slotted spoon and drain on a plate lined with paper towels.  Repeat with the rest of the chicken.  (Optional: To get the chicken extra crispy, allow the chicken to drain and cool for 5 minutes, then put the chicken back in the wok to fry for about another 30 seconds, until golden brown.)
6. Transfer the oil to a heat-proof container.  Leave a light coating of oil in the pan, and heat over medium-high heat until a bead of water sizzles and evaporates on contact.  Add the chilies and garlic and stir just until fragrant, about 20 seconds.  Pour in the sauce mixture and heat briefly to thicken.
7. Return the chicken to the wok and stir well to coat with sauce (I didn't think there would be enough sauce, but keep stirring, and it will cover.).  Transfer the chicken to a serving dish.  Garnish with sesame seeds and scallions and serve.