Wok-Seared Chicken with Mustard Greens and Spicy Soy Sauce

This dish seems a bit more Chinese to me than Indian, but the mix of flavours results in a rich, spicy dish. As a warning, I should mention I found this spicy and flavourful while having a massive head cold. This is definitely not a child-friendly dish.

Wok-Seared Chicken with Mustard Greens and Spicy Soy Sauce (from 660 Curries)

Ingredients
1 tbsp tomato paste
1 tbsp soy sauce
1/2 tsp coarse salt
1/4 tsp five-spice powder
450g boneless, skinless chicken breasts, cut into 1/2" cubes
1 tbsp cornstarch
8 tbsp peanut or canola oil
225g mustard greens, rinsed, finely chopped, and patted dry
2 large garlic cloves, finely chopped
3 - 5 fresh green Thai, cayenne, or serrano chiles, cut in half lenghtwise, stems removed
2 tbsp finely chopped cilantro
3 scallions, cut into 2" lengths

1. Stir tomato paste, soy sauce, salt, and five-spice powder together in small bowl.
2. Toss chicken and cornstarch together in medium bowl.
3. Heat wok or cast-iron skillet over high heat. Drizzle 2 tbsp oil down sides. Add chicken and stir-fry until chicken turns reddish-brown and is cooked through, 5 - 8 minutes. Transfer to plate.
4. Trickle 2 more tbsp of oil down wok, add half of mustard greens. Stir-fry until wilted, 2 - 4 minutes. Add to chicken. Repeat.
5. Drizzle remaining 2 tbsp oil into work and stir-fry garlic and chiles (may sure the area is ventilated). Add tomato paste mixture and stir to warm it, 30 seconds.
6. Return chicken and greens to wok and stir to combine, 2 - 4 minutes.
7. Stir in cilantro and scallions and serve.