Cheesy Shredded Potato Casserole (with Low-fat Option) + Giveaway! Pre-heat oven to 375 F. Grease a 13 x 9 inch casserole dish with butter or oil and set aside. Boil potatoes in a large pot of boiling water until fork tender (about 10 minutes). Drain potatoes and allow to cool until they are easy to handle.
While the potatoes are boiling, Whisk the cream cheese, sour-cream, milk, butter, garlic powder, salt and pepper. Add in the shredded potatoes, 1/2 cup cheddar cheese, 1/2 cup mozzarella cheese, and green onion. Stir mixture with a wooden spoon until well combined. Pour mixture into casserole dish and top with remaining cheese.
While the potatoes are boiling, combine sour-cream, cream cheese, butter, and milk in a large bowl. Season with salt pepper and garlic powder. Add in the shredded potatoes, shredded cheddar and mozzarella cheese, chopped green onion and transfer to a baking dish. Sprinkle with more cheese and bake for 30-40 minutes or until cheese is bubbly.
Reduce oven temperature to 350 degrees F (175 degrees C). Butter a casserole dish. Scoop potato flesh into a bowl; discard skins. Add Cheddar cheese, sour cream, 1/4 cup butter, milk, cream cheese, chives, salt, garlic salt, and pepper. Mash mixture until combined and potatoes are still slightly lumpy.