Marinate the pork

Place cubed pork in a medium bowl and season with salt, sugar and soy sauce before mixing in egg whites and green onions. Cover and place in the fridge for 1 hour.

Heat the oil

In a large deep pan or deep-fryer, heat the vegetable oil to 185°C.

Remove the pork from the fridge and coat in cornflour. Fry the pork in the hot oil for about 10 minutes – until evenly browned. Drain pork on paper towel and set aside.

Cooked the vegetables

In a wok over medium heat, heat a little oil and stir in celery, pepper and onion. Cook until the vegetables are tender then remove from heat and set aside.

To make the sauce

Mix the water, salt, sugar, apple cider vinegar, ketchup and soy sauce in a large saucepan over high heat. Bring to the boil then stir in the cooked pork, vegetable mixture and contents of pineapple can.

Thicken the sauce

Bring sauce to a boil before stirring in cornflour and water mixture to thicken. Cook for a further 5-10 minutes until shiny and thick.