Spiced sweet potatoes

Cook the onion in 2 tablespoons of the olive oil until golden. Add the potatoes and pour in water, barely covering the potatoes. Bring to the boil, then reduce to a simmer.

Add the ginger, cumin, paprika, a pinch of salt and another 2 tablespoons of oil. Cook until the potatoes are tender, mixing every once in a while.

Add the lemon juice, the rest of the oil, olives and the chopped parsley. Serve at room temperature.