Put the tomatoes in a mixing bowl with the scallions and drained cannellini beans.
Season with sea salt and a little freshly ground black pepper; then drizzle with some extra virgin olive oil and the vinegar and mix to combine.
Heat a frying pan (without any oil - chorizo simply does not need it) and add the chorizo.
Cook gently for a couple of minutes on each side. The chorizo will secrete a lot of oil. Do not throw it away! It is delicious if you want to fry a few potatoes in it. Or, add some of the oil to the salad!
To serve; transfer the tomato, bean and onion mixture to a serving dish and top with the hot chorizo. Scatter over the chopped parsley and serve at once.