Drain beets. Reserve 1/2 cup liquid. Cut in 1/4 inch strips. Set aside.
In large skillet, over medium high heat, saute potatoes in 2 Tbsp. oil til golden brown and just tender, about 10 minutes. Add corned beef and onion. Saute til crisp.
Stir in the sliced beets, the chopped parsley and reserved beet liquid. Preheat oven to 400.
With large spoon, scoop out four 3 inch rounds of has. Crack an egg into a custard cup. Side egg into an indentation in has. Repeat with remaining eggs. Bake til eggs are set, about 15 minutes. Sprinkle eggs with cheese. In small bowl, mix sour cream and horseradish. Serve with hash. Serves 4