In a large mixing bowl, combine pork, sugar, five spice , salt and vinegar. Marinate for a least 30 minutes.
To make the batter, in a bowl, add plain flour, corn flour, egg yolks. Slowly add milk, whisking continuously, until mixture is fairly thick and all lumps are removed.
Heat oil in a fry pan or wok to around 180C. Sprinkle the marinated pork with pepper. Dip pieces of meat into the batter, tapping on the side of the bowl to remove any excess.
Carefully drop battered pork pieces, one by one into the pan. Cook in batches for 5 minutes or until crisp and golden. Transfer meat to a paper towel and set aside.
To make the sauce, heat remaining oil and fry garlic, ginger and chilli until aromatic.
Add carrot, red onion, green and red capscium, stirring constantly. Season with a little salt and pepper and return pork pieces to the pan. Stir through spring onions, coriander and tomatoes. Pour over vinegar, soy sauce, tomato sauce and lemon juice. Add cornflour mixture and simmer for about a minute or until the sauce begins to thicken.
serve with steamed rice.