Cut the pork tenderloin, against the grain, into either ¼ inch strips or bite-sized chunks. Place in a medium bowl with cornstarch, soy sauce, and one tablespoon oil. Mix well to coat and set aside for 15 minutes while you prep the rest of the ingredients.
1 pound pork tenderloin, 2 tablespoons cornstarch, 1 tablespoon peanut oil, 1 tablespoon soy sauce
Add the sauce ingredients to a small bowl and mix together. A whisk is helpful to fully incorporate the thick oyster sauce. Set the sauce aside.
2 inch fresh ginger, ¼ cup oyster sauce, 1 tablespoon sugar, 1 tablespoon toasted sesame oil, 2 tablespoons soy sauce, 1 tablespoon white vinegar, ½ cup chicken broth
Heat the cooking oil in a large skillet on medium-high heat. Add the coated pork in a single layer, separated as well as you can. Let the pork cook for 4-5 minutes without stirring, until it is deep golden-brown underneath. Use tongs to transfer the partially cooked pork to a large plate or shallow bowl, leaving as much oil behind as possible.
3 tablespoons peanut oil for cooking
Cook the peas in the same pan, tossing occasionally. Cook for about 3 minutes until some of the peas are blistered in spots. Then transfer the peas to the plate with the pork.
8 ounces sugar snap peas
Add the onion to the pan and cook about 3-4 minutes. Add a splash of oil if the pan seems dry. Once the onion is softened and beginning to brown, add the minced garlic. Stir and cook for one minute, then reduce heat to medium.
1 medium yellow onion, 6 garlic cloves
Add the pork and peas back to the pan and pour in the sauce. Stir and cook for about a minute, until the meat is cooked through and the sauce is thick and clinging to the meat and vegetables.
Serve with steamed rice, cauliflower rice, or just as-is.