Tortilla española (Spanish omelette)

Spain's national dish: eggs, potatoes, olive oil and, if you are on team cebollista, onion. The debate over onion is eternal; what is not negotiable is slowly poaching the potatoes in oil instead of frying them hard, and leaving the centre slightly juicy.

Ingredients

• 5 medium potatoes (about 700 g), peeled and thinly sliced
• 1 large onion, thinly sliced (optional but recommended)
• 6 large eggs
• 300 ml mild olive oil (you will reuse most of it)
• 1 tsp salt

Method

1. Heat the oil in a deep frying pan over medium heat. Add the potatoes (and onion) and cook gently for 20-25 minutes, turning occasionally, until completely tender but not browned.
2. Drain well (keep the oil for your next tortilla) and season with salt.
3. Beat the eggs with a pinch of salt in a large bowl, add the warm potatoes and onion, and rest for 10 minutes so the egg soaks in.
4. Heat 2 tablespoons of the reserved oil in a 20-22 cm non-stick pan. Pour in the mixture and cook on medium-low for 4-5 minutes, shaking the pan so it does not stick.
5. Place a large plate over the pan, flip the tortilla onto it in one confident move, slide it back in and cook 3-4 more minutes. For a juicy centre, serve it slightly underdone in the middle.

Tips

• The flip is easier if the pan is no wider than the plate.
• Tortilla is served hot, warm or cold - in Spain it is normal at any temperature, in a wedge, in a sandwich (bocadillo) or as a tapa.