Spring brings with it wild garlic, asparagus, the first peaches and, of course, the opportunity to go for a picnic! One of my favourite weekend activities in the spring is cycling far into the Dutch countryside, armed with a selection of delectable treats to unpack upon arrival. Roast vegetable sandwiches with a hot-pepper mayo, scotch eggs, fresh fruit, sparkling lemonade, and the queen of all picnic dishes in my household: Spanish tortilla!

Tortillas in Spain are quite unlike their Mexican namesakes. They are instead a sort of omelette, filled with potatoes and onions that have slowly cooked in olive oil, sometimes embellished with other simple ingredients such as asparagus, which I feature here today. The beauty of a well-made tortilla is that it tastes even better cold and it’s perfectly portable, two qualities that make it the ideal picnic food.

A sort of omelette

Heat the oil in a large frying pan (non-stick, preferably) over medium heat. Add the onion and potato slices, season liberally with salt and mix well so that all slices are coated in oil. Cook for about 15 minutes, until the vegetables are softened but not browned.

In the meantime, peel the bottom third of the asparagus, discarding any tough ends, and chop in 3-4 cm pieces. Add to the frying pan and season with ground black pepper. Toss in the oil and cook for another 4-5 minutes until the vegetables are just starting to colour (adjust the heat accordingly).

In a bowl, beat the eggs with a couple of pinches of salt. Pour the eggs into the pan and mix into the potato slices so the mixture is evenly distributed.

Leave it to rest

Let it cook so that the egg sets over medium-low heat, regularly lifting the side of the tortilla and allowing any remaining runny egg to flow into the gaps for another 3-4 minutes. The top will still be very runny by the time the bottom has caramelised, so, as a final step, place the frying pan under a pre-heated grill for 2 minutes so that the top sets and browns lightly (a little wobble in the middle is not a bad thing).

Leave the tortilla to rest for a couple of minutes in the pan before gently upturning it onto a cutting board (a spatula can help persuade the tortilla to slide out). Slice it into wedges and marvel at the mosaic-like beauty of your lunch, or cut it into large cubes and serve as a tapa with some wine. Or, as I usually prefer, pack into your picnic basket and ride with it until your hunger gets the better of you.

Anastasios Sarampalis is a lecturer at the Psychology Department.