Heat oil in a large, heavy-based saucepan on medium. In batches, sauté chicken pieces for 5 minutes, turning, until golden. Set aside. Add capsicum and cook for 1 minute, until soft. Set aside. Add onion and cook for 2 minutes, until soft. Stir in rice and cook for 1 minute.
Mix in stock and saffron. Season to taste and bring to boil. Return chicken pieces to saucepan. Top with capsicum, reduce heat and cover. Cook gently for 15 minutes, until tender. Add peas and cook for another 5 minutes. Serve.