Patatas a lo Pobre, also known as Papas a lo Pobre is a very simple potato and pepper dish from Andalusia in the south of Spain. The name means Poor Man's Potatoes, and like many peasant dishes, its simplicity is what makes it wonderful.
Heat the olive oil in a large frying pan on medium heat. Peel and finely chop the onion and add to the oil to sauté for about 5 minutes without browning. Crush the garlic cloves and throw them in the pan with their skins on. Peel and cut the potato in half lengthways, then cut into slices about 5mm (quarter of an inch) thick. Add them to the pan along with a pinch of salt, stir everything until it's well coated in oil, cover and cook for 15-20 minutes, until the potatoes are tender.
Chop the pepper into small pieces, and when the potatoes are cooked, add them to the pan to cook for about 5 minutes. Stir in the vinegar and cook for 2 minutes more.
You can eat this on its own, as a side dish with chicken or with a big slab of jamón.