I started with the sauce:
Chopped up the veggies and the pork:
Added everything to the skillet, and voila!
Sweet and Sour Pork
1 pound pork tenderloin, cut into 1/2 inch pieces
2-1/2 Tablespoons balsamic vinegar **See update below**
2 teaspoons low-sodium soy sauce
1 Tablespoon cornstarch
3 Tablespoons ketchup
3 Tablespoons sugar, plus a pinch
3 Tablespoons peanut or vegetable oil
3 cloves garlic, minced
2 carrots, thinly sliced
3 scallions, cut into 1/2 inch pieces
3 cups snow peas, cut in half
Toss the pork with 1/2 Tablespoon vinegar and a pinch of salt in a bowl. Mix the remaining 2 Tablespoons vinegar, the soy sauce, cornstarch, ketchup, 3 tablespoons sugar, 1/3 cup water and half teaspoon salt in another bowl.
Prepare carrots, scallions and snow peas.
Heat 2 Tablespoons oil in a large wok or skillet over high heat. Add the pork and slowly stir until it turns mostly opaque, about 2 minutes. Remove the pork with a slotted spoon and transfer to a plate. Discard the oil and wipe out the skillet.
Heat the remaining 1 Tablespoon oil in the skillet, then stir fry the garlic with a pinch each of salt and sugar, only 15 seconds or it will burn. Add the carrots and scallions and stir-fry until crisp tender, 2 minutes. (If it seems dry and a little bit of water, just a little. Add the pork, snow peas and soy sauce mixture; stir until the pork is cook through and the sauce is thickened, about 3 minutes.
** Update ** Try using either rice vinegar or regular white vinegar instead of balsamic. I did this on accident and actually preferred the taste!