Bring a pan of water to the boil and cook the rice for 10-12 minutes, or according to packet instructions.
Drain the rice and return to the pan. Stir in the pepper slices, sugar snap peas, parsley, soy sauce and seasoning and heat gently.
For the fish, heat the oil in a non-stick frying pan and sear the seasoned mackerel fillet for two minutes on each side. Add the lemon juice to the pan and heat for another minute.
Remove the fish from the pan and transfer to a serving plate.
Add the wine and cream to the pan in which you cooked the fish and reduce for a few minutes, to thicken.
Spoon the rice alongside the fish and drizzle the sauce over to serve.