Spain's national culinary symbol: tender, slow-confit sliced potatoes and sweet caramelised onions bound in softly set free-range eggs with a juicy, creamy centre (jugosa).
Heat olive oil in a 24cm non-stick skillet over medium-low heat. Add sliced potatoes and onion with 1 tsp salt. Poach gently for 20-25 minutes, turning occasionally, until potatoes are tender and break easily with a spatula without browning.
Drain potatoes and onion in a colander, reserving the fragrant oil. In a large bowl, beat the eggs lightly with a pinch of salt. Add warm drained potatoes and onions, gently pressing down. Let sit for 10 minutes so eggs absorb starch.
Heat 1 tbsp reserved oil in the skillet over high heat. Pour in the egg mixture. Swirl the pan and run a spatula around the edge for 1-2 minutes until bottom sets.
Place a flat plate over the pan, flip confidently, and slide back into the pan. Tuck edges underneath and cook for 1-2 minutes more for a moist, juicy centre. Slide onto a plate and rest 10 minutes before slicing.