Cheesy Rosemary Mashed Potato Casserole
How does velvety smooth, fluffy mashed potatoes with a crispy Parmesan and breadcrumb topping and hint of rosemary flavor sound? That perfectly describes my Cheesy Rosemary Mashed Potato Casserole, the perfect side dish for family meals or the holiday season. You can even prep it ahead.
This is one of my ‘oldie but goodie’ recipes from 2017 that I just refreshed with a new video.
The best mashed potatoes are the ones that are as smooth and creamy as they can be. These particular ones are made with heavy cream, melted butter, two cheeses (white cheddar and mozzarella), and the addition of fresh rosemary—like posh mashed potatoes and my kind of comfort food.
I turned them into a casserole because the addition of panko breadcrumbs and Parmesan is the proverbial cherry on the cake.
This is the only mash potatoes recipe you need and this is a potato side dish that will be the first to disappear at the dinner table. You could call this the ultimate mashed potatoes that are baked in a casserole dish. Whether you’re making a Sunday family meal, Thanksgiving or Christmas, this easy recipe can be prepared up 2 days in advance, refrigerate in the casserole dish and bake right before serving.
Best Potatoes for this Mashed Potato Recipe
Any potatoes you like. Russet potatoes, Yukon gold potatoes or red potatoes. Jersey royals or King Edwards if you’re in the UK and even yams and sweet potatoes.
How to get the Smoothest Mash
I do not own a potato masher. I prefer to mash my potatoes through a potato ricer. There are never any lumps and the result is a smoother texture, when then leads to a creamier texture when milk and cheese are added (which is the ultimate goal). A food milll is also a great option. I never use an electric mixer or food processor as over mixing the potatoes can make them gummy.
Cheesy Rosemary Mashed Potato Casserole Cheese
There are three cheeses in these creamy mashed potatoes: white cheddar, mozzarella, and Parmesan in the crispy topping. A good, sharp white cheddar adds amazing flavor, the mozzarella adds creaminess (and that irresistible cheese pull), and the Parmesan brings a nutty flavor to the panko breadcrumb topping.
Different Cheeses for Mash
Blue cheese would bring a delightful tangy element, goat cheese or cream cheese for an extra creamy element.
Optional additions to Potato Casserole
Sour cream, roasted garlic, Greek yogurt, green onions/scallions, the possibilities are almost endless.
How to Make the Creamiest Potatoes
Heavy cream is the key. You can also use whole milk, but you wont achieve the velvet, creamy texture that you get with the cream.
Secret to the Best Mashed Potatoes
When boiling potatoes for mash, it’s best to ensure they are well-dried after draining. This can be easily done by placing the drained potatoes back into the hot pan to evaporate any excess liquid. This helps make them fluffier when mashed.
If you don’t want to boil potatoes, I also have a very handy way of making Microwave Mashed Potatoes.
Panko Breadcrumb Topping
To gild the lily, the breadcrumb topping mixed with Parmesan cheese adds a crispy, golden crunch that perfectly complements the creamy mash.
How to Boil Potatoes Evenly
By adding the potatoes to cold water and bringing them up to temperature with the water, you ensure they cook evenly and perfectly through until fork-tender.
How to Serve Mashed Potato Casserole
This was just one of two side dishes I served with Herb Roasted Beef Tenderloin, Slow Cooker Green Beans, and Creamy Horseradish Sauce. You can see them all above.
If you’ve made this Cheesy Rosemary Mashed Potato Casserole or any other recipe, leave a comment or question below. I love to hear from my readers and feedback is very important.
Cheesy Rosemary Mashed Potato Casserole
The ultimate, creamy mashed potatoes with cheeses, rosemary and a panko, Parmesan topping.
Ingredients
- 5 pounds (2.2 kg) potatoes of your choice, peeled and quartered
- 2 tablespoons salt
- 2 cups (473 ml) heavy/double cream, warm
- ½ cup (113 grams) unsalted butter, melted
- 1 cup (83 grams) white cheddar cheese, grated
- 1 cup (83 grams) mozzarella cheese, grated
- 2 tablespoons fresh rosemary, chopped
- ½ teaspoon ground black pepper
- 1 cup (108 grams) panko breadcrumbs
- 1 cup (83 grams) Parmesan cheese, grated
Instructions
- Add the potatoes to a large pan and cover with water. Bring to a boil, add the 2 tablespoons salt and simmer for 15 minutes until tender when a fork is inserted. Drain and add to a large bowl. Transfer back to the hot dry pan (to allow the potatoes to dry out).
- Preheat oven to 375°F/190°C.
- Butter the inside of a 9 x 13-inch/23 x 33 cm/4 quart casserole dish.
- Run the potatoes through a ricer or food mill or mash really well to get the smoothest mash possible.
- Add the cream, butter, cheeses, rosemary and pepper. Stir until combined and the cheese is melted. Taste and add salt if needed (I did not since I added it to the boiling water as well as the cheeses have salt).
- Pour the mash into the casserole dish and spread evenly. If making ahead, cover at this stage without the breadcrumbs and refrigerate. Bring to room temperature before adding the breadcrumbs then baking.
- To freeze ahead, cover the casserole well. The day before you’re ready to bake, take it out of the freezer and thaw in the fridge overnight. Make sure you bring it to room temperature before baking (this is important if it is in the baking dish so it is not too cold for a hot oven). This is a good time to prepare the panko topping, then bake.
- Mix the breadcrumbs and Parmesan in a bowl. Sprinkle an even layer of breadcrumbs and Parmesan cheese on top of the mashed potato.
- Bake for 30 minutes until the top is golden.
Nutrition Information
Yield
8Serving Size
1Amount Per Serving Calories 778Total Fat 46gSaturated Fat 28gTrans Fat 1gUnsaturated Fat 14gCholesterol 135mgSodium 1299mgCarbohydrates 74gFiber 7gSugar 6gProtein 21g
This nutrition calculation is provided by Nutronix that is only a guideline and not intended for any particular diet.
6 Comments on “Cheesy Rosemary Mashed Potato Casserole”
Question: Can it be prepared without the topping, then frozen? I would like to make it a couple of weeks ahead.
This dish is perfect to make ahead. Prepare it up to step 6 then you can either freeze it in the dish you’re going to bake it in, or a container that will fit in your freezer. The day before you’re ready to bake, take it out of the freezer and thaw in the fridge overnight. Make sure you bring it to room temperature before baking (this is important if it is in the baking dish so it is not too cold for a hot oven). This is a good time to prepare the panko topping, then bake per the recipe. I’ve added these instructions to the recipe. Enjoy! Let me know if you have any more questions.
Lovely and creamy mash and the crispy panko topping is perfect. Will make this again for the holidays.
This is one of my favorites
So good. I love the combination of smooth mash with the crunchy topping
Thank you, I’m glad you enjoyed it.