Wash and peel your potatoes and slice lengthwise.
Slice your potatoes into 1/4" thick slices or you can slice using a mandoline. Soak your potatoes while we prepare our other ingredients.
Slice your onion the same thickness as your potatoes and set aside.
Heat your pan on medium heat and add in your pancetta. Cook for about 5 minutes or until browned and add in your garlic once the pancetta is browned and cook for an additional minute. Drain the fat and set aside.
Beat your eggs and add in 1/4 tsp of salt. Keep in mind the pancetta is salty so we don't want to over salt.
Drain your potatoes and pat dry. Add 1/2 tsp of salt, onion powder, garlic powder, and dry chives.
Add your olive oil to your pan on medium high heat and heat for 1 minute. Add in your potatoes and bring the heat down to medium. You want a slow boil not a fry. We want our potatoes to be tender to the fork but not crispy.
Cook for 5 minutes then add in your onion and cook for an additional 4 minutes or until the potatoes are tender.
Strain your onions and potatoes. Note: You can strain your olive oil and save it.
Add your potato onion mixture to your eggs and gently fold to combine. Typically, you allow it to rest for 15 minutes but if you're in a pinch for time you can cook it right away.
Heat your pan on medium high heat and add in half your mixture. Cook for about 1 minute and turn the heat to medium.
Top with your pancetta and mozzarella, then with the rest of your egg potato mixture. Cook for 5 minutes, using your spatula to make sure it doesn't stick to the sides.
Then, using kitchen gloves, place a large plate over the pan and flip your tortilla.
Cook for an additional 5 minutes and flip and serve.
I love to top mine with some chives and serve with a nice salad.