Peel and wash the potatoes. Halve the potatoes by piercing each one with the point of the knife and pulling it apart with the hands. This method eases the release of the starch, which will made the sauce thicker and smoother. Reserve.
Peel and cut the onion, the garlic and red pepper in small pieces and let cook with generous olive oil spurt at medium/low heat. When ready (onion is transparent) add the chorizo and stir for 1 minute.