Boil soya chunks in plenty of water until fully soft. Drain and let cool.
Squeeze the soya chunks firmly with both hands to remove as much water as possible.
In a bowl, combine soya chunks with paprika, black pepper, salt, and 1 tablespoon (8 g) of cornflour. Toss to coat evenly.
Heat 1 tablespoon (15 ml) of olive oil in a pan over medium heat. Add coated soya chunks and fry for 2 to 3 minutes, stirring regularly, until lightly golden. Remove and set aside.
Add the remaining 1 teaspoon (5 ml) of olive oil to the same pan. Add white and light green spring onion parts and stir for 30 seconds.
Add onion cubes, capsicum cubes, and green chilli. Cook on medium-high heat for 2 minutes, keeping the vegetables firm.
Add tomato ketchup, soy sauce, and vinegar. Stir well and cook for 1 minute.
Mix the remaining 1 tablespoon (8 g) of cornflour with 3 to 4 tablespoons (45 to 60 ml) of water in a small bowl until smooth.
Pour the slurry into the pan and stir constantly. Add a splash of water to keep the sauce at a medium, flowing consistency.
Add the fried soya chunks back in. Toss to coat in the sauce and cook for 2 more minutes.
Taste and adjust salt. Turn off heat. Garnish with green spring onion tops and serve hot.