Preheat the oven to 425° F. Cut each potato into 8 wedges and place in a bowl with the oil, paprika, and salt. Toss well together, arrange on a sturdy baking sheet and cook for 20 minutes, turning occasionally.
Scatter over the grated cheese and scallions and return to the oven for a further 10 minutes until the cheese is melted and bubbly and the wedges are nicely browned.
Meanwhile, make the dip by stirring together the sour cream, scallions, and horseradish sauce.
Spoon into a serving bowl, place the bowl into the center of a large plate, and arrange the cheesy wedges and serve hot.
Servings: 4