Peel and cut potatoes into squares, the smaller the better.
Heat pan and add enough oil to coat the bottom of the pan, add the potatoes, onion, peppers and celery and cook on med low heat with a lid. Let potatoes cook for a few then stir. Replace lid and let cook for a few more minutes. You want your potatoes to start to get soft and cook all the way through.
After they are cooked, turn up the heat and fry to desired texture -- I like mine on the crispy side.
Move the potatoes to the edges of the pan and add the chorizo to the pan. Turn up the heat to med-high. The chorizo will start to disolved and melt into a chunky sauce. Stir with the potatoes and cook for a few minutes longer to make sure the chorizo is cooked.