Peel and chop the potatoes into even chunks.
Boil the potatoes in salted water until tender, about 15-20 minutes.
Drain the potatoes and return them to the pot.
Add butter and milk, then mash until smooth.
Stir in salt, pepper, cheese, bacon, and green onions until just combined.
Preheat the oven to 375°F (190°C).
Spoon the potato mixture into a greased baking dish, creating a well in the center.
Fill the wells with your stuffing of choice (additional cheese, meats, or vegetables).
Top with extra cheese and a sprinkle of green onions.
Bake for 25-30 minutes until golden and bubbly.
