Easy tortilla

Method

1. Thinly slice the potatoes with a mandoline or a very sharp knife. Fry them in the oil until golden and crispy all over. Set aside.
2. Caramelise the onion in the butter until very dark brown. Add a little water to deglaze any burnt parts when overly brown.
3. Mix the eggs with the caramelised onion and the crisped potatoes, season to taste with salt and leave it to rest in the fridge for an hour.
4. Meanwhile, heat a non-stick frying pan to a medium/hot heat, add a splash of the olive oil and pour in the egg and potato mixture. After two minutes turn over the omelette using a plate larger than the pan. Repeat this process after two minutes and again until the omelettes are nicely browned. The centre of the omelette should retain runny consistency.