Spinach and onion tortilla

Method

1. Preheat the grill to high. Crack the eggs into a large bowl, season and beat briefly with a fork.
2. Heat the oil in a large frying pan with an ovenproof handle and fry the onion until soft and pale golden. Add the spinach and sauté for a couple of minutes to wilt the leaves.
3. Pour the egg mixture into the pan, turn the heat down to its lowest setting and cook the tortilla, uncovered, for about 8 minutes, until there is only a little runny egg left on the top.
4. Sprinkle the grated cheese over the top and melt under the preheated grill for 1-2 minutes, until the top is golden and bubbling.
5. Use a palette knife to slide the tortilla out onto a plate. Cut into wedges. Leave to cool and store in the fridge, ready to box up for lunch.