Parboil the potatoes in a pan of salted boiling water for 5 to 6 minutes, or until almost cooked through. Drain and leave to steam dry.
Cut the chorizo into 2cm chunks and place in a large non-stick ovenproof frying pan. Cook in the hot oven for a couple of minutes to render out the fat and give it a bit of colour. Carefully pull out the pan, give it a jiggle and add the sliced pepper. Return to the oven for 1 to 2 minutes, or until the pepper starts to soften. Add the potatoes and tomatoes to the pan and give it a good shake so that everything gets coated in all the lovely chorizo oil. Return to the oven for 2 to 3 minutes, or until everything is cooked through and nicely coloured.
Remove the pan from the oven and use the back of a spoon to make four wells in the mixture. Crack your eggs, one by one, into the wells. Season with salt and pepper, then return the pan to the oven for about 2 minutes (depending on how you like your eggs). Keep a close eye on the pan and pull it out as soon as the eggs are done to your liking. Scatter with chopped parsley, then take the pan to the table for everyone to tuck in. Serve with hunks of crusty bread.