Mix the soy sauce, 2 tablespoons of the olive oil, salt and paprika in a bowl.
Slice the chicken into strips across the grain and add to the soy sauce mixture. Mix well and set aside to marinate.
Chop the capsicum into small pieces and slice the spring onions into 3cm lengths. In a frypan or wok, stir fry the capsicum in the remaining tablespoon of oil about 3 minutes. Add the spring onions and the chicken and stir fry until chicken is nearly cooked.
Drain the pineapple juice from the pieces into a bowl. Add the cornflour to the juice and mix well. Add the pineapple pieces to the chicken in the frypan and cook two more minutes. Add the pineapple juice/cornflour mixture to the pan and bring to the boil. Simmer for 3 minutes until the sauce thickens, and serve!