Sweet & Sour Pork

Cut the pork tenderloin into 1-inch cubes, ensuring uniform size for even cooking. Pat the pork cubes dry with paper towels to remove excess moisture, which helps achieve better browning. In a medium bowl, whisk together flour, cornstarch, salt, and black pepper to create the coating mixture. In a separate small bowl, beat the egg until smooth. Dip each pork cube first in the beaten egg, then roll in the flour mixture until completely coated on all sides. Heat vegetable oil in a large skillet or wok over medium-high heat until shimmering but not smoking. Carefully add the coated pork cubes to the hot oil in a single layer - don't overcrowd the pan or the temperature will drop. Fry for 3-4 minutes per side until golden brown and crispy on all surfaces and cooked through (internal temperature should reach 145°F). Remove the fried pork with tongs and place on a paper towel-lined plate to drain excess oil.

Remove most of the oil from the skillet, leaving about 1 tablespoon for stir-frying the vegetables. Add the red bell pepper, green bell pepper, and onion chunks to the hot skillet and stir-fry over medium-high heat for 3-4 minutes until the vegetables are crisp-tender but still have some crunch. Add the minced garlic and stir-fry for another 30 seconds until fragrant. Add the pineapple chunks and cook for 1 minute more to warm through. While the vegetables cook, prepare the sweet and sour sauce in a small saucepan by whisking together ketchup, rice vinegar, brown sugar, and soy sauce. In a small bowl, mix the cornstarch with water to create a slurry, then whisk this into the sauce mixture. Bring the sauce to a simmer over medium heat, stirring constantly, and cook for 2-3 minutes until thickened and glossy.

Return the crispy fried pork cubes to the skillet with the stir-fried vegetables and gently toss to combine. Pour the hot sweet and sour sauce over the pork and vegetables, using tongs or a spatula to gently fold everything together until all pieces are evenly coated with the glossy sauce. Be careful not to break up the crispy coating on the pork while mixing. Cook for 1-2 minutes more to heat everything through and allow the sauce to cling to all the ingredients. Taste and adjust seasoning if needed - you can add a pinch more brown sugar for sweetness or a splash more vinegar for tang. Transfer the sweet and sour pork to a serving platter and immediately garnish with sliced green onions and sesame seeds for color and extra flavor. Serve hot while the pork is still crispy and the sauce is glossy. This dish is perfect over steamed rice or enjoyed on its own as a complete meal.