Happy Call Pan Recipe - Spanish Omelette

Ever since my trip to Barcelona, the simple Spanish Omelette has caught my attention as a beautiful breakfast food or tapas item. I have been thinking of recreating this dish for ages but because of the huge size of the dish it took a party to make an attempt at it. I used little oil with the base from an earlier steaming of sausages and wiped the top part of Happy Call Pan later with Olive Oil when I had to flip. Enjoyed this meal a lot, tho it I think I have to experiment again to make this thicker, and add more oil. 

Ingredients
5 large eggs 
1 tablespoon water to egg (recommended by expert) 
5 potatoes
1 onion
Salt and pepper to taste

Directions
Chop up onion and potatoes
Fry both till soft on low heat till almost cooked
Add in egg mixture (egg, salt, pepper, water)
When cooked, scrape base to allow an easier flip to other side

Lessons learnt
Some recommend to take potato and onion out and coat in egg mixture
Better use oil on both sides so won't stick
If the pan stuck flip back again at the end to show the nicer side