In a small bowl, whisk together mayonnaise, chili sauce, parsley, onion, horseradish, Worcestershire, lemon juice, salt, and pepper. Set aside.
Working on a clean work surface, spread about 1 teaspoon butter evenly on each slice of bread. Turn slices over and spread with prepared dressing. Onto four of the slices top with equal amounts of Toma, sauerkraut, corned beef. Top each sandwich with remaining bread slices.
Heat a 12-inch skillet or griddle over medium heat, add sandwiches, working in batches, as needed. Cook sandwiches, pressing down frequently, until golden brown and crisp, about 5 minutes. Turn sandwich, continuing to press, and cook until the other side is brown and crisp and cheese is melted, about 5 additional minutes. Cut in half and serve hot.
