1. For the meatballs, combine the minced meat with the onions, rolled oats and salt. Shape into 12 oblong meatballs. Brown the butter in a frying pan over medium-high heat, then cook the meatballs for approx. 14 minutes, turning occasionally to brown all sides.
2. To make the raspberry dressing, mash the raspberries and whisk in the vinegar, sugar, salt and pepper. Season the dressing with more pepper – it should be spicy.
3. Press salt into the cabbage until it softens slightly to make it easier to eat. Arrange the cabbage, cucumber slices and cranberries on a bed of spinach leaves. Pour a little dressing over and garnish with fresh raspberries. Serve the salad with the rest of the dressing, warm meatballs and lightly toasted rye bread.