This recipe holds a special place in my heart. Not only was it passed down from a family friend (a woman who was born & raised in Madrid, Spain), but something that's so iconic to the Spanish eating/tapas experience. We've been lucky enough to visit Spain on a number of occasions (my husband & I also studied there for a period in high school) & I worked at a bomb Spanish tapas restaurant during college (shoutout to Toro Boston). After eating my share of the good, bad & ugly when it comes to tortilla I've noticed a few things: the iconic tortilla is browned on the outside & slightly oozy in the middle, it's perfectly sweet and savory, has a beautiful golden color, and the potato to egg ratio is well balanced.
Tortilla normally sits like a beautiful disk on the counter of any Spanish tapas bar (room temperature) - since European egg processors do not wash the eggs prior to sale - leaving the outer layer of the shell (the cuticle) intact, eggs can safely remain at room temperature. In the US, eggs must be washed prior to sale (removing the cuticle), requiring them to remain refrigerated throughout their storage process. Therefore, when American restaurants serve tortilla, it must remain refrigerated through serving. I find this often causes the tortilla to dry out, and doesn't catch the essence of the oozy/caramelized texture. To counteract the American egg processing, I opt for pasture raised or free range eggs when making this dish, and add in additional yolks for that extra "custardy" texture. The Contented Hen Free Range Eggs I found at my local Trader Joe's are a great option. Try them out or let me know about your other favorite egg brands in the comments. If you're lucky enough to get your hands on some fresh eggs, go that route!