Learning Chinese Cuisine (1) Northeastern Fried Pork with Sweet and Sour Sauce

1️⃣ Step 1: 300-500g of tenderloin, vegetables, cut ginger into thin strips, scallions into thin strips, carrots into thin strips, coriander stems, and garlic slices.
2️⃣ Step 2: Slice the tenderloin into thin pieces about 3mm thick (cut slightly larger pieces) and tenderize them with the back of a knife. Marinate with a small half teaspoon of salt for 10 minutes. Then add potato starch, adding a little water in batches and mix evenly. The ratio of water to starch is about 1:1, forming a thick yogurt-like consistency (remember, only meat coated with potato starch will be tender and not tough; it should not be too runny and must coat evenly).
3️⃣ Step 3: Heat oil in a pan, add the meat slices one by one, waiting for each to set before adding the next. Fry until fluffy and white, then remove. Once the oil heats up again, fry a second time until golden, then remove.
4️⃣ Step 4: Prepare the sauce: 2 tablespoons sugar, 50ml white vinegar (adjust according to meat quantity and taste), a small half teaspoon of salt, a small half teaspoon of light soy sauce (the sourness should be higher than the sweetness; after mixing, you can test with chopsticks).
5️⃣ Step 5: Leave a little oil in the pan used for frying meat. Over low heat, add the vegetables, carrots, ginger, and garlic slices; stir-fry until fragrant. Add the fried meat, pour the prepared sauce along the edge of the pan to allow it to evaporate slightly (do not pour directly on the meat). Add coriander and scallion strips, turn to high heat, quickly stir twice, and serve immediately (do not stir-fry too long or it will become soft).