1 (1 ounce) square unsalted butter, chilled and minced
1 cup diced water chestnuts
2 cups loosely packed chopped onion
1 green bell pepper, seeded and chopped
1 1/2 cups cooked, diced potato
1/2 cup milk
1/2 teaspoon salt
1 (8 ounce) package cream cheese, softened
1 cup shredded Cheddar cheese
1 cup shredded Swiss cheese
Dredge the water chestnuts in the unsalted butter.