In a medium pan, bring salted water to the boil. Add rice, reduce heat, cover and simmer for 20 minutes.
While rice is simmering, combine prawns, ginger, red chilli powder, garlic, sesame seeds and black pepper in a large plastic bag. Allow to marinate in the refrigerator.
Heat sesame oil in a large frying pan. Add red capsicum and green onions; stir-fry 3 to 4 minutes to soften slightly. Add teriyaki sauce. Add peas and prawns; stir-fry 4 minutes or until prawns are opaque.
Stir cornflour into chicken stock and add to pan; cook, stirring until mixture boils. Sprinkle with salt. Spoon prawn mixture over rice.