This is not an authentic recipe but it hits the spot.
For 4 servings you need:
700g new potatoes, cooked and cut into large chunks
1 onion, sliced
2 tbsp tomato puree
4 tbsp sherry
2 tsp paprika
1/2 tsp ground cumin
2 tsp chilli flakes
salt and pepper
2 tbsp red wine or sherry vinegar
Begin by sauteeing the cooked potatoes in a pan over a high heat to give them some colour. This takes about 10 mins. Add all the remaining ingredients and cook out for a further 5 mins or so. You want the potatoes covered in the sauce, but no sauce left in the pan. Serve warm or cold.