Make-ahead sides like this Cheesy Mashed Potato Casserole are an absolute life saver. Chunks of potatoes cooked in salted water until tender, then whipped until creamy. They’re then mixed with onion and chive cream cheese, butter, half and half and shredded cheese and placed into a dish for baking. Dot the top with butter and more cheese then watch this goodness disappear.
Not only for entertaining but, on days you know you’re going to be on the run and will need to pull dinner together in a snap. Potatoes go with almost everything and I don’t believe I’ve ever met anyone who doesn’t love them. Baked, smashed, fried, boiled, roasted or mashed they’re delightful. When I was growing up Sunday dinner would have never been served without a heaping dish of creamy mashed potatoes. We enjoyed Sunday pot roast almost every week after church and mashed potatoes were a given covered in gravy, of course. It’s in the Southern Sunday dinner rule book, they just had to be included on the menu.This cheesy mashed potato casserole can easily be customized to your taste, changing up the flavor of the cheese. You can use whatever flavor of shredded cheese that’s your favorite. When my friends at Cabot Cheese sent their sharp white cheddar to me to try, I knew it would compliment the flavor so beautifully. This dish proves that food doesn’t have to be fancy to be scrumptious. If you’re making this mashed potato dish in advance and chilling, it’s ideal to set the casserole on the counter for 20-30 minutes to allow the potatoes to come to room temperature prior to baking. It’s also perfectly fine to bake them from cold just increase the baking time 10 minutes or so and you’ll be good to go.
You may also like: Irish Colcannon Potatoes, Instant Pot Scalloped Potatoes and Slow Cooked Cheesy Ranch Potatoes.
Disclosure ~ If a purchase is made using one of the affiliate links on this website we may earn a small commission at no additional cost to you. Thank you!
Helpful Kitchen Items:
Cheesy Mashed Potato Casserole
- 5 lb russet potatoes peeled and cubed
- 1  oz onion and chive cream cheese softened
- 1/2 cup plus 2 Tbsp butter softened and divided
- 1 cup half & half lukewarm
- 1 1/4 tsp garlic salt
- black pepper to taste
- 3 cup shredded sharp white cheddar cheese [i.e. Cabot Sharp White Cheddar]
- Butter the bottom and sides of a 7x11-inch casserole dish and set aside.
- Cook the potatoes in salted water until fork tender. Around 15 minutes. Drain well.
- Place cooked potatoes in a mixing bowl and use a hand mixer to whip in the cream cheese, 1/2 cup butter, garlic salt and black pepper. Add the half & half 1/4 cup at a time, until you reach the desired consistency. Adjust the amount as needed. Whip until smooth. The potatoes should feel soft and will firm as they chill. Taste and adjust the salt and pepper to your taste.
- Stir in 2 cup shredded white cheddar cheese by hand. Pour into the buttered casserole dish. Sprinkle with the remaining 1 cup shredded cheese. Dot the top with 2 Tbsp butter. Cover with plastic wrap and chill if making in advance.
- To prepare: Remove from the fridge and bring to room temperature. Preheat the oven to 350°F. Bake for 40-45 minutes until heated through and the top is golden.
If baking from cold, increase the baking time by 10-15 minutes