Step 1
To make the romesco sauce, place all of the ingredients in a blender or food processor with a good pinch of salt. Process until the mixture is a rough paste, you may need to scrape down the sides and then mix again.

Step 2
In a large frying pan, heat a film of olive oil over medium heat. Cook the potatoes in batches until they are golden and just tender. Turn at times. This may take about 10 minutes. Once done, transfer the potatoes to a plate and set aside.

Step 3
In the same pan, add the sliced chorizo sausage and cook until it becomes slightly crisp. Remove the chorizo from the pan and set aside with the potatoes.

Step 4
Add the remaining olive oil and to the pan and cook the onion and garlic for 5 minutes and then mix in the paprika.

Step 5
Whisk the eggs and milk together in a large bowl. Season with salt and pepper. Add the potatoes, chorizo and cheese to the beaten eggs. Mix everything together until all the ingredients are evenly coated.

Step 6
Pour the egg mixture back into the pan with the onions. Cook the tortilla over medium-low heat for about 8-10 minutes or until the edges begin to set, and the centre is slightly runny.

Step 7
Preheat the oven grill, slide the pan under the grill and cook the tortilla until it is set through and golden on top.

Step 8
Serve the tortilla sprinkled with parsley, a good dollop of romesco sauce and rocket leaves alongside.