Next to paella, tortilla española or tortilla de patatas is one of the most famous national dishes of Spain. It can be found on restaurant menus, but it is also served as tapas. Patatas means potatoes, and that about sums it up: this is a type of omelette (similar to an Italian frittata) filled with potatoes. Tortilla española can be made with or without onions. I prefer with, as it adds depth of flavor.

The Dutch word for french fries is “patat” and I remember my parents coaxing me into ordering tortilla de patatas when I was a child by telling me there were french fries in there. This is in fact not far from the truth, because the potatoes are cooked in a lot of oil before they are added to the omelette. The main difference is that they are poached in the oil rather than fried, so the potatoes do not become very crispy. You only need 4 or 5 ingredients to make this: eggs, potatoes, olive oil, salt, and the optional onions. As usual with simple recipes like this, the quality of the ingredients is what can make or break this dish. As can the technique, because you don’t want the eggs or potatoes to be undercooked or overcooked. Don’t be put off by the huge amount of olive oil, because most of the oil will be strained and can be used for another preparation (or for the next time you’re making this). Here is how to make a perfect tortilla española…

Ingredients

For 4 servings as a full meal or 16 servings for tapas

1 kilo (2.2 lbs) waxy potatoes

8 eggs

half a litre (2 cups) extra virgin olive oil

3/4 tsp salt

1 large onion (optional)

Instructions

Peel a kilo of potatoes.

Cut the potatoes in half or in quarters lengthwise if needed, then slice them about 3 mm thick (1/8 inch).

The potato slices should be of uniform size and thickness to ensure even cooking.

Heat half a litre of olive oil in a non-stick pan. (I did not use non-stick, and regretted it.)

Add the potatoes when the oil is around 120C/250F. You want the potatoes to sizzle only slightly in order to poach rather than fry them in the oil.

Mince a large onion (if using), and add to the potatoes.

Cook the potatoes, stirring regularly, until they are tender but firm to the bite, about 20 minutes.

Meanwhile, break 8 eggs into a large bowl.

Beat the eggs until the whites and yolks have been mixed completely.

When the potatoes are ready…

…strain as much olive oil as possible from them using a colander or large sieve. Reserve the oil for a future use.

When the potatoes have cooled somewhat (so they won’t cook the eggs prematurely), add them to the bowl with the eggs, season with 3/4 tsp salt (5.5 grams)…

…and stir to incorporate.

Heat 2 tablespoons of the reserved olive oil in a 28 cm (11 inch) non-stick frying pan. When the oil is very hot, pour in the egg and potato mixture.

Use a spatula to level the egg and potato mixture in the pan. Cook over medium-high heat…

…covered…

…for about 3 minutes. The top should start to solidify.

Lightly oil a large flat plate that is big enough to cover the frying pan, and put it on top.

Turn the pan with the plate upside down, using oven mits.

Return the pan to the heat, and slide the tortilla from the plate into the pan.

Cook on the other side over medium-high heat for 3 minutes, or until the tortilla is just cooked through.

Serve warm or at room temperature. Once cooled off, the tortilla will keep for several days in the refrigerator. It heats up well in a microwave (that is how most bars in Spain do it, too).

Flashback

Béarnaise is one of the classic sauces from French cuisine and it is great with steak. The traditional way of preparing it au bain marie requires quite a bit of skill, as the sauces curdles easily. It also requires you to make clarified butter first. And even though you should make clarified butter to cook the steak anyway, using a slightly different technique you can make sauce béarnaise easily with minimal risk of curdling.