3 pounds potatoes, peeled and cut into 1/2-inch cubes
3 medium carrots, shredded
3 celery ribs, trimmed and diced
1 medium onion, diced
2 cups shredded sharp cheddar cheese, divided
1/2 cup butter, cubed
4 ounces cream cheese, softened
1/4 cup plus 1 tablespoon minced fresh parsley, divided
1/2 teaspoon salt
1/2 teaspoon pepper
1/4 cup chopped ripe olives
Preheat oven to 350°. Place potatoes, carrots, celery and onion in a Dutch oven; add water to cover. Cook, covered, until vegetables are almost tender, 8-10 minutes. Drain. Return to Dutch oven; toss with 1-3/4 cups cheddar cheese, butter, cream cheese, 1/4 cup parsley, salt and pepper.
Transfer to a greased 13x9-in. baking dish. Top with olives and the remaining cheese. Bake, uncovered, 15-20 minutes or until bubbly and the cheese is melted. To serve, sprinkle with remaining parsley.