1. Preheat your oven to 375°F (190°C). Lightly grease a 9×13-inch baking dish to prepare for the casserole.
2. Place the peeled and diced potatoes in a large pot and cover with cold water. Add a pinch of salt. Bring to a boil over medium-high heat, then reduce to a simmer and cook until the potatoes are tender when pierced with a fork, about 15-20 minutes.
3. While the potatoes cook, fry the bacon slices in a large skillet over medium heat until crispy, about 6-8 minutes. Transfer the bacon to a paper towel-lined plate to drain and cool. Once cool, crumble the bacon into bite-sized pieces. Tip from Mama Lou: Don’t toss the bacon fat — save a tablespoon for extra flavor in the potatoes if you like!
4. Drain the potatoes thoroughly and return them to the pot. Add the butter, sour cream, milk, minced garlic, and half of the shredded cheddar cheese. Mash everything together until creamy and smooth. Adjust the texture with a little more milk if needed.
5. Season the mashed potatoes generously with salt, black pepper, and smoked paprika if using. Stir in the crumbled bacon (reserve some for topping) and chopped green onions.
6. Spread the mashed potato mixture evenly into the prepared baking dish. Sprinkle the remaining cheddar cheese and reserved bacon on top for a golden, bubbly finish.
7. Bake in the preheated oven for 20-25 minutes, until the cheese is melted and the top is lightly browned and crispy.
8. Remove from the oven and let it rest for 5 minutes before serving. This helps the casserole set and makes it easier to scoop.

One thing I’ve learned from cooking alongside Ouma over the years is that letting the casserole rest before serving makes all the difference — the flavors meld together, and the texture becomes just right. Don’t rush it!