Pour the olive oil into a large skillet and set it over medium heat. Add the chorizo, breaking it into small pieces with a wooden spoon, and cook until it starts to turn golden and release its fat, about 5 minutes. Add the jalapeños and cook for 1 minute.
Stir in the tomatoes and garlic, and increase the heat to high (the tomatoes should bubble). Add the sugar and chili flakes. Leave the tomatoes to bubble and lose a bit of their moisture for about 5 minutes. Stir and season with salt and pepper to taste.
Make 4 wells in the mixture and crack an egg into each well. Leave them to cook gently until the whites are solid.
Sprinkle the feta and parsley over the eggs. Serve with a dollop of sour cream on top, if you like.
