In a pan add some oil and add onion, cabbage, potatoes and some salt. Saute well. Cover and cook for 5 minute.
In a bowl add the eggs, pepper powder and salt. Beat them well.
To this beaten egg add the cooked veggies and mix them well.
In a pan add some oil . Pour half of the egg veggie mix.
To this add the grated mozzarella cheese and then pour the remaining egg veggie mix.
Cook it for 2 minute . Take a plate and place it on top of the pan, flip it over to the plate.
Turn it and put into the pan to cook the other side. Cover and cook it for 3 minutes. Spanish omelette is ready.