Lovely one pot dish that puts chorizo and sweet potatoes together like they should be. Don't use thin-sliced chorizo for this, it needs to be in meaty little chunks. Oh and don't add any salt either, the chorizo brings lots of saltiness to the sauce. Serves 2, takes about 40 to 45 mins.
Dice the onion and start it frying gently with a good slug of olive oil, in a large deep pan for which you have a lid. While the onion is softening, chop the chorizo into rough little pieces (roughly 1cm square but no need to be accurate), then add it to the onion. Similarly, slice the chilli finely and throw that in. Shuffle the stuff around a bit and put the lid on, let it continue to sweat a bit, frying gently with the lid on.
Wash and peel the potatoes and chop them into medium chunks, then add them to the mixture and stir. Turn the heat up to medium, add the tinned tomatoes and stir, then let the mixture come back up to temperature (i.e. the tomatoes need to heat up). Then add the wine and mix it in. Add a bit of black pepper if you like.
Let the mixture bubble gently for 30 minutes. (The time is needed for softening the potatoes but also for getting the chorizo to melt a bit and soften up.) At some point, check and see if it needs a little bit of boiling water to add a bit more liquid.
Just before serving, wash the parsley and stir it through the mixture.