If you're not using a pressure cooker for the rice, refer to package instructions. Of course you may substitute your favorite rice as well...
I'm all about portion control. We typically do 4 to 6 ounces of lean protein. I have specified 12 ounces for this recipe, and it serves 2 generous or 3 smaller portions.
You can substitute pork, turkey, chicken, even tofu for the beef.
This combination of veggies works well time-wise. Both the peppers and the bok choy require only 2-3 minutes in the wok. If you use harder vegetables, that step will require additional cook time.
I love to use Fresno chile to get the heat in a stir fry, but I can't always find them. You can add a teaspoon +/- sriracha or chile paste to the marinade instead.