Shepherds Pie

Name: Shepherd's Pie
Ingredients: 4 cups Beef Stew with Beer and Paprika, recipe follows; Horseradish Mashed Potatoes, recipe follows, to cover the stew; 3 tablespoons olive oil; 1 tablespoon salted butter; 2 pounds beef stew meat, cut into 1-inch cubes; 1 medium onion, diced; 3 cloves garlic, minced; 2 heaping tablespoons all-purpose flour; 3 cups beef stock; One 12-ounce can beer; 2 tablespoons tomato paste; 1 tablespoon Worcestershire sauce; 1 1/2 teaspoons sugar; 1/2 teaspoon paprika; 1/2 teaspoon kosher salt; Freshly ground black pepper; Minced fresh parsley, optional, for serving; 5 pounds russet or Yukon gold potatoes, peeled and cut into chunks; 2 sticks salted butter, at room temperature; One 8-ounce package cream cheese, at room temperature; 1 cup heavy cream; 1 tablespoon horseradish cream; 1/2 to 1 teaspoon seasoned salt; 1 teaspoon freshly ground black pepper; 1/4 cup finely chopped fresh parsley