Cut the steaks into bite-sized pieces. Cut the peppers into small pieces. Chop the onion or cut it into small cubes.
Melt the margarine in a roaster and sear the steak pieces. Meanwhile, cook the rice separately. After the steak pieces are crispy, add the onions and fry them too, but don`t let them turn black. After the onions have reached the desired browning, add the corn (cooked!), Bell peppers, mushrooms, kidney beans and peas to the roasting pan and fry them as well.
Finally, the finished rice is placed in the roaster, mixed well with the other ingredients and lightly seared again.