Egg Omelette Recipe

1 large raw potato ( 1 cup )( kachcha aloo you can use boiled as well )
1 large onion ( 1 cup )
1 cup cabbage ( optional )
1/4 cup oil
1/2 tsp salt
3 eggs
1/2 tsp salt
1/2 tsp pepper powder
Coriander or mint leaves
1/2 cup cheese ( optional )