Recreating New York street vendors' "halal chicken over rice" New York City is filled with carts selling all sorts of food, but the most common ones are the halal carts. They each have their own recipes, but all have the same basic signature dishes: chicken or lamb, over rice or in a pita, with optional "white sauce" and "hot sauce." The lamb is generally gyro meat, but the chicken is something unique... chunks of white and dark meat marinated in a rich, flavorful blend of generically middle eastern spices, sauteed and chopped up. The rice is usually either a bright yellow or an even brighter orange.

I'm wondering how I might make this at home: what spices might I put on the chicken? What's the white sauce? What's the hot sauce? What's in the rice? I'm usually good at figuring out spices, so I'd expect to find the flavor of cumin, cinnamon, coriander, and the like, but I can't make out a single distinct flavor in the delicious blends used at most of these carts! The only hint I have is the whole cardamom pods I've occasionally bitten into.

(I've tried asking, but the vendors invariably lose their understanding of the english language at precisely this moment :)
My guess is that the chicken is a variation on chicken kebabs. These are often made by marinating the chicken in yogurt with garlic and turmeric. The same technique can be used for chicken on the bone. 

I'm not sure for the rice -- maybe someone else can help out?

The hot sauce is most likely harissa. This is a generic term for a number of spicy sauces used in the middle east and northern Africa. The basic recipe is dried chilies, other spices, and olive oil. Here are some variations. 

There is also a Yemenite hot sauce known as skhug or zhug. (It may also be known in Israel by the generic name Harif, which means spicy or sharp. Note the same root as Harissa.) This can be green or red or even brown, depending on ingredients. Green zhug is often made with cilantro, while the brown one includes tomatoes. The red one includes red peppers.  

The white sauce is probably a variant on yogurt sauce, such as labneh. This is often combined with garlic and a green herb such as parsley.