Bake the Potatoes

1. Preheat Oven: Preheat your oven to 400°F (200°C). Line a baking sheet with foil or parchment paper.
2. Prepare Potatoes: Poke holes in each potato with a fork to allow steam to escape. Place the potatoes on the prepared baking sheet.
3. Bake: Bake for 45–60 minutes, or until the potatoes are tender when pierced with a fork. Remove from the oven and let them cool slightly.

Scoop and Mash

4. Scoop the Flesh: Slice each potato in half lengthwise. Use a spoon to scoop out the flesh, leaving a thin layer inside the skins to help hold their shape if desired. Transfer the potato flesh to a large mixing bowl.
5. Mash the Potatoes: Add butter, sour cream, milk, garlic powder, onion powder, salt, and black pepper to the potato flesh. Mash until smooth and creamy. Adjust seasoning as needed.

Assemble the Casserole

6. Mix in Toppings: Stir in 1 cup of shredded cheddar cheese, ¼ cup of crumbled bacon, and 2 tablespoons of green onions into the mashed potatoes.
7. Transfer to Dish: Spoon the potato mixture into a greased 9×13-inch casserole dish, spreading it out evenly.
8. Top with Cheese and Bacon: Sprinkle the remaining ½ cup of cheddar cheese and ¼ cup of bacon over the top.

Bake the Casserole

9. Bake Again: Reduce the oven temperature to 375°F (190°C). Bake the casserole for 20–25 minutes, or until heated through and the cheese is melted and bubbly.

Garnish and Serve

10. Add Final Touches: Sprinkle with the remaining green onions before serving. Serve hot with optional sour cream on the side.