Add the pork into a bowl and sprinkle the salt. Mix to make sure the salt is evenly spread throughout the salt. Leave the pork to marinate for at least 10 minutes on the counter.
While your meat is resting on the counter, prep your dredging station with three separate bowls. In the first bowl, add 1/2 c (or 62.5 grams) of the cornstarch.
In the second bowl, add the egg and lightly beat with a whisk or fork.
In the last bowl, combine the rest of the cornstarch, the all-purpose flour, and salt.
First, dip the pork cubes into the first bowl of cornstarch and properly cover them completely in the starch until they are white. Place them on a cooling rack and repeat the process with the rest of the meat. Allow the cornstarch covered meat to rest on the cooling rack for about 5 minutes before moving on. This soaks up excess water in the meat and allows the batter to stick better to the meat.
Then take the pork cubes covered in cornstarch, dip them into the beaten egg, and immediately cover them with the cornstarch and all-purpose flour mix (the contents of the third bowl). Place it on the cooling rack and repeat with the rest of the pieces. Let all the meat rest coated in dredging for at least 10 minutes to allow the crust to stick to the meat.
While you wait for your pork dredging to rest, preheat your frying oil. In a heavy-bottomed pot over medium-high heat, add enough vegetable oil to cover about 1 ½ to 2 inches above the bottom. Preheat the oil to 375°F.
First fry: After resting, carefully lower the pork pieces into the oil and fry for about 2 minutes per batch, occasionally turning them over to make sure both sides evenly fry. Try not to crowd the pork and pot by adding too many pieces. I add about 5 pieces at a time. Remove the pork when it’s pale in color and measures 145 °F in the center using the instant-read thermometer. The crust should be slightly crispy. Transfer to a paper towel-lined, clean cooling rack to remove excess oil. Repeat frying for the rest of the pork. In the photo-- left: pork fried once, right: fried twice
Second fry: Carefully lower the fried pieces of pork back into the oil and continue to fry for about 2 minutes or until they become light brown and measure about 200 °F. The color will get slightly darker after you remove them from the oil. Remove them from the oil and place them back onto the cooling rack. Continue to fry the rest of the meat a second time until complete.
In a saucepan over medium heat, add the garlic oil and sauté for about 30 seconds or until it’s nice and fragrant. Add the tomato sauce, apple cider vinegar, and sugar into the pan and stir until combined.
In a separate bowl, combine the cornstarch and water until fully incorporated. Add this mixture to the saucepan and cook on medium-high until it hits a boil. Bring the heat to medium for a simmer and continue to stir until the consistency is similar to maple syrup which takes about 8 minutes. The sauce should be a darker orange-red at this point. See photo for how the final texture should look.
Add the msg at this point and taste. Adjust any flavors however you prefer. If you want it sweeter, add sugar, or if you want it tangier add more vinegar.
Add the onion and cook for about 1 minute, then add the bell pepper, pineapples which don’t need cooking. Mix to coat in the sauce.
Add the fried pork pieces and stir until you’ve covered the fried pork pieces. There should be just enough sauce to cover the fried pork, but not that it’s dripping with sauce. Serve immediately.