Step 1:

• In a large bowl, season the pork pieces with salt and pepper.
• Dredge each piece in flour, then dip into the beaten eggs, and coat with cornstarch. This will ensure a crispy coating when fried.

Step 2:

• Heat the vegetable oil in a large pan or wok over medium-high heat.
• Once the oil is hot, fry the pork pieces in batches until golden brown and crispy.
• This should take about 4-5 minutes per batch.
• Remove the pork with a slotted spoon and drain on paper towels.

Step 3:

• In a separate pan, combine the rice vinegar, ketchup, sugar, and soy sauce.
• Bring the mixture to a boil over medium heat, stirring until the sugar has dissolved.
• Add the cornstarch mixture to the sauce, stirring constantly until it thickens.

Step 4:

• Add the bell peppers, onion, and pineapple chunks to the sauce, cooking for about 3-4 minutes until the vegetables are tender but still crisp.
• Add the fried pork pieces to the pan, tossing everything together to coat the pork evenly with the sauce.