Everything you love about a loaded baked potato, turned into the creamiest make-ahead side dish. Fluffy mashed potatoes blended with sour cream and cream cheese, topped with sharp cheddar, crispy bacon and green onion, then baked until golden and bubbly. It's the holiday side everyone fights over — and the best part is you can assemble it the day before and just bake it off when you're ready.
Fun fact: adding cream cheese to mashed potatoes is a classic make-ahead trick. The fat and acidity keep the potatoes creamy and prevent them from drying out or turning gluey when reheated — which is exactly why this casserole holds up so beautifully when assembled ahead.
Why this recipe works
- CREAM CHEESE + sour cream. They make the mash ultra-creamy and keep it from drying out when baked.
- WARM dairy. Adding warm milk and butter keeps the potatoes silky, never gluey.
- BACON and cheese on top. Baking the toppings on top gives crispy bacon and a bubbly golden cheese crust.
Nutrition information
- Calories: 390 kcal per serving
- Protein: 12 g
- Carbohydrates: 34 g
- Fat: 24 g
- Saturated Fat: 12 g
- Fiber: 3 g
Pro tips for the best cheesy bacon mashed potato casserole
- Use starchy potatoes. Yukon gold or russets mash up the fluffiest and creamiest.
- Don't overmix. Mash just until smooth; overworking releases starch and turns potatoes gluey.
- Make ahead. Assemble (without baking) up to a day ahead, refrigerate, then bake — add 10 minutes from cold.
- Warm the dairy. Cold milk seizes the starch; warm milk and butter keep the mash silky.
Frequently asked questions
Can I make mashed potato casserole ahead?
Yes — it's designed for it. Assemble without the final bake, cover and refrigerate up to 24 hours, then bake (add about 10 minutes since it starts cold).
Can I freeze it?
Yes — the cream cheese helps it freeze well. Freeze before baking up to 1 month; thaw overnight and bake.
What potatoes are best?
Yukon gold for buttery creaminess, or russets for the fluffiest mash. Avoid waxy potatoes, which can turn gummy.
How do I reheat leftovers?
Cover and reheat in a 350°F oven until hot, or microwave individual portions. Add a splash of milk if it's dry.
Can I make it without bacon?
Yes — it's still delicious. Add extra cheese, chives or caramelized onions for flavor instead.
