Cantonese Chicken and Mushrooms

1 1/4 lbs chicken tenders or skinless, boneless chicken breasts, cut into 1 1/2-in pieces
1/2 cup oyster sauce
2 Tbs cornstarch
2 Tbs peanut oil (if you're like me and don't want to buy a bunch of oils you'll never use, you can use vegetable oil, or sesame oil)
6 scallions, cut into 1-in pieces
8 thin slices peeled ginger
3 cloves garlic, coursely chopped (more if you want)
8-10 oz sliced mushrooms
12 oz baby bok choy, cut crosswise into 1 1/2-inch pieces
1 1/4 cups chicken broth
2 tsp toasted sesame oil (I will say you should probably get sesame oil, it gives it a little extra flavor, and a bottle will last you a long time)
Cooked rice, for serving

1. Toss the chicken with the oyster sauce in a bowl.  (I'm gonna warn you, this is probably going to smell very bad, but trust me, it's a very good dish) Mix the cornstarch with 3 Tbs cold water in another bowl.  Place both bowls near the stove (or wok, whatever you're cooking with), with the remaining ingredients.

2. Heat a wok or deep skillet over high heat until hot.  Add the peanut oil, then the scallions, ginger and garlic, and stir-fry about 20 seconds.  Add the chicken mixture and stir-fry until the meat is no longer pink on the outside, 2 to 3 mins.  Stir in the mushrooms and bok choy.

3. Add the broth and sesame oil to the skillet and bring to a boil over high heat.  Add the cornstarch mixture, return to a boil and cook, tossing, until the chicken is cooked through and the sauce is thick and glossy, 2 to 3 mins.  Serve with rice