1Set a large lidded skillet over medium heat and add the chorizo. Cook, stirring now and then, for 3 to 4 minutes until it has released its red oil and the edges are lightly crisp. Lift the chorizo out with a slotted spoon and set it aside, leaving the fat in the pan.
2Add the olive oil to the skillet and raise the heat to medium-high. Add the potatoes in an even layer with a good pinch of salt. Let them sit without stirring for 4 minutes so the bottoms start to brown.
3Stir the potatoes, turn the heat down to medium, cover and cook for 8 minutes until they are tender when poked with a fork.
4Uncover, add the onion and bell pepper, and cook for 8 to 10 minutes, stirring only every minute or two, until the potatoes are crisp and golden and the vegetables are soft.
5Stir in the garlic and smoked paprika and cook for 30 seconds until fragrant. Return the chorizo to the pan, splash in the sherry vinegar, scrape up any browned bits, and season with salt and pepper.
6Use the back of a spoon to make four shallow wells in the hash and crack an egg into each. Season the eggs with a little salt and pepper, cover and cook for 3 to 5 minutes, until the whites are set and the yolks are still runny.
7Scatter the parsley over the top and serve straight from the skillet.