1. Place the potatoes in a large saucepan and add cold water to cover. Bring to a boil and add a little salt. Cover and reduce the heat to medium. Cook at a brisk simmer for 20-30 minutes, or until tender.

2. Drain well. Return to low heat and stir for a minute or two to evaporate excess liquid.

3. Add the cream, milk, and butter and mash. Add the Cheddar, scallions, parsley, chives, and horseradish and mix well. Season with salt and pepper and serve hot.