Peel, wash and pat dry 3 yukon gold potatoes, cut each one into 4 evenly sized quarters, cut each quarter into 3 pieces and then slice into 1/8 inch (.3175 cm) thick pieces, finely dice 1 large onion, grab 2 cups of tightly packed fresh spinach and roughly chop, shred 2 cups of Manchego cheese, crack 6 eggs into a large bowl and season with sea salt & black pepper, whisk together until well combined

Heat a large nonstick fry pan with a medium heat and add in a generous 1/3 cup of extra virgin olive oil, after 2 minutes add in the diced onions and mix with the olive oil, after 2 minutes add in the pieces of potatoes and continue to mix, after 20 to 25 minutes and the potatoes are fully cooked through, start adding the spinach into the pan, add in batches to not over-fill the pan, mix the spinach with the potatoes so it wilts, once all the spinach has been incorporated and wilted, turn off the heat, season everything with sea salt & black pepper, mix so the seasonings are evenly mixed

Add the potatoe mixture into the bowl with the eggs, add the 2 cups of shredded Manchego and mix everything together until well combined, at the same time, make sure to heat the same fry pan with a low to low-medium heat

Once well mixed, add the mixture into the pan, make sure everything is in a single layer, after 2 minutes run a spatula through the outer edges to ensure the mixture is not sticking to the pan

After 4 to 5 minutes it´s time to flip the tortilla to cook the other side, add a plate that is a little smaller than the pan into the pan, place one hand over the plate and the other hand on the handle, make the flip in one swift motion, slide the tortilla back into the pan, push down on the tortilla to ensure everything is evenly divided and then using the back of a spatula, start compacting the tortilla through the outer edges and into the middle, this gives it that classic rounded edge

After another 4 to 5 minutes the tortilla should be perfectly cooked, remove from the heat and transfer into a serving dish, enjoy!