1. peel and slice the potatoes into 2mm thick slices. 2. Fry the potatoes in a pan with plenty of olive oil until golden brown. 3. Peel and slice the chistorra sausage, then sauté in a hot pan without oil for 5 minutes and set aside. 4. In a separate bowl, add the eggs and mix with a whisk. 5. Once the potatoes are golden brown, drain the oil and add them directly to the hot eggs. 6. Add salt, caramelized onions, and mix well with the eggs, potatoes, and chistorra. let the mixture rest for 10 minutes to achieve a creamy texture. 7. In a hot pan with olive oil, add the mixture and shake the pan. cook for 1 minute over medium heat. 8. Flip the tortilla and cook for another minute over medium heat, then transfer to a plate. 9. Finally, cut a generous slice of the tortilla and enjoy.