Boil the Potatoes:
Place the peeled and cut potatoes in a large pot and cover them with cold water. Bring to a boil and cook for 15-20 minutes, or until the potatoes are fork-tender. Drain the potatoes and return them to the pot.
Mash the Potatoes:
Using a potato masher or hand mixer, mash the potatoes until smooth and creamy. If you prefer ultra-smooth mashed potatoes, use a hand mixer or potato ricer.
Add the Creamy Ingredients:
Add the butter, cream cheese, sour cream, and milk to the mashed potatoes. Stir until fully incorporated and creamy. Season with salt and pepper to taste.
Stir in the Bacon and Cheese:
Mix in 1 cup of shredded cheddar cheese and crumbled bacon. Reserve a little cheese and bacon for topping the potatoes later.
Transfer to a Serving Dish:
Transfer the mashed potatoes to a serving dish or casserole dish. Top with the remaining cheese, bacon, and chopped green onions.
Bake (Optional):
For an extra cheesy, crispy topping, you can place the loaded mashed potatoes in a preheated oven at 350°F (175°C) for about 10-15 minutes, or until the cheese is melted and bubbly.
Serve and Enjoy:
Garnish with extra green onions or a dollop of sour cream if desired. Serve hot and enjoy the ultimate loaded mashed potatoes!