Chilli Prawns (Shrimp Manchurian)

Name: Chilli Prawns (Shrimp Manchurian)
Prep time: 30 min
Cook time: 20 min
Total time: 50 min
Cuisine: American
Ingredients: 250 grams (8 to 12 large) deveined prawns ((9 ounces shrimp)); 1½ tablespoon sugar; ½ teaspoon salt (preferably sea salt); 1 cup water; ¼ teaspoon black pepper; 2 tablespoon corn flour ((corn starch)); 2 tablespoon all purpose flour; 1½ tablespoon oil (to fry); 1 tablespoon olive (or sesame oil for sauce); ½ cup capsicum (cubed bell peppers); ¼ cup spring onions ((greens & whites separated or ½ cup cubed onions layers separated)); 1 tablespoon (4 medium) garlic (coves chopped ); 1 to 2 green chili (slit ); 1½ tablespoon Asian Chili sauce ((Sweet and hot)); 1 to 1½ teaspoon soya sauce ((low salt)); 1 to 1½ teaspoon rice vinegar ((or apple cider vinegar)); 1 teaspoon red chili powder (mixed with 2 tbsps water or 1 tbsp chili paste (optional)); ½ teaspoon black pepper ( crushed); ½ teaspoon sugar