To prepare a mom's stir fry sweet and sour pork rice recipe, first you'll need to prepare the pork chops. You can use any type of pork that you like, as long as it hasn't been smoked or otherwise treated with antibiotics or hormones, or if you prefer, you can substitute another pork cut, such as pork shoulder, for the shoulder. If you want to use pork tenderloin, cut it into bite-sized pieces. Then, add the chopped onions, garlic, ginger, and soy sauce to the pot and stir to combine. Cook the mixture over medium-high heat, stirring occasionally, until the vegetables are tender and the meat is no longer pink in the center, about 5 to 7 minutes. Remove the pan from the heat and set aside.