Rakott Krumpli (A Hungarian Casserole)

INGREDIENTS

• 2 pounds Large Red Potatoes
• 3 Tablespoons Vegetable Oil
• 2 whole Large Sweet Onions, Thinly Sliced
• 3 whole Eggs
• 12 ounces, weight Cooked Keilbasa, Sliced
• 1 dash Salt And Pepper
• 2 cups Sour Cream
• 1 cup Sharp Cheddar Cheese, Shredded
• 2 Tablespoons Butter, For Greasing Baking Dish