Cheddar Shortcakes with Corned Beef Hash

Ingredients

1 cup sour cream

3/4 cup water

3 cups all-purpose flour

1 1/2 teaspoons baking powder

1 teaspoon baking soda

1 1/2 teaspoons salt

3 tablespoons cold unsalted butter, cut into bits

6 oz sharp Cheddar, coarsely grated (1 1/2 cups)

For hash

2 lb yellow-fleshed potatoes such as Yukon Gold
2 onions, coarsely chopped
3/4 stick (6 tablespoons) unsalted butter
2 red bell peppers, coarsely chopped
1 lb (1/8-inch-thick) slices cooked corned beef, cut crosswise into 1/8-inch-wide strips
1 teaspoon salt
1/2 teaspoon black pepper
1/2 cup minced fresh flat-leaf parsley