Cheesy Rutabaga Gratin

Rutabaga Gratin is a side dish that will make everybody’s eyes light up when you serve it.  In this delicious casserole, tender chunks of peppery rutabaga are smothered in a creamy cheddar and gruyere sauce and baked until bubbly and browned on top.

Topping vegetables with a creamy cheese sauce, like a classic green bean casserole, is an easy way to get your family saying “Yes please!” to a generous helping of veggies, and even asking for seconds!

Overview of baked rutabaga gratin garnished with thyme.

What is a Rutabaga?

Rutabagas are a root vegetable in the cabbage family with a yellowish-orange flesh, and a sweetness and bite similar to but slightly stronger than turnips, which have white flesh.

In fact, a common question is “What is the difference?”. Both have purple tops, but turnips tend to be smaller and cleaner in appearance. Rutabagas often look like they’ve been knocked around a bit, but those scars are all erased once you peel them.

Rutabaga has a spicy, pungent edge that pairs well with a smooth creamy cheese sauce!

 

How to Prepare Rutabaga Gratin

You’ll want a sharp knife and a safe technique. Here’s how to peel, prep, and keep your fingers intact.

  • Cut off bottom and top to prepare a flat surface.
  • Stand on end and slice off strips all the way around (or use a vegetable peeler).
  • Flip to the other flat edge and remove the rest of the peel.
  • Cut into bite-size cubes, and simmer in water until partially cooked.

Two images showing cheese sauce ingredients in a pot and rutabaga cubed in a strainer.

How to Make Rutabaga Gratin

With the rutabaga prepped and parboiled you are ready to make a cheesy rutabaga casserole in 3 simple steps!

  1. Cheese Sauce: Make the seasoned cheese sauce, starting with a roux.
  2. Combine: Place parboiled rutabagas and diced onion in a casserole dish and pour the sauce over.
  3. Cook: Bake until fragrant, bubbling and golden brown on top.

Two images showing the prepared cheese sauce pot and then poured over the rutabaga.

Once you have the basic idea, go ahead and experiment. You can soften rutabagas’ bite by combining with equal parts of potato or turnip cubes. Brussel sprouts or broccoli can add some extra color. Plus their flavors are complementary to rutabagas and equally enhanced by cheese.

Alternatively, you could slice the rutabagas thinly instead of cutting into cubes, and layer the slices with the sauce, scalloped potato style. If you go this route, don’t parboil.

Can You Freeze Rutabaga Gratin?

This is one dish you probably want to leave out of the freezer. That smooth and luscious cheese sauce is likely to separate and get gummy when thawing.

  • Leftovers will keep in the fridge for up to four days.
  • Reheat in the microwave or with a foil cover in the oven, to prevent the top from burning.

More Cheesy Sides Please

We love serving roasted root vegetables and dishes like brown sugar roasted rutabaga, but there is something irresistible about covering veggies in a creamy cheese sauce!

You will definitely want to make extras when serving side dishes like cheesy broccoli casserole or a classic potatoes au gratin for supper!

Rutabaga Gratin

Cheesy and delicious side dish perfect for the holidays.

  • 3 1/2 to 4 lbs rutabaga (cubed)
  • 1/2 cup onion (chopped)
  • 3 tablespoons butter
  • 3 tablespoons flour
  • 1/2 teaspoon thyme
  • 2 cups milk
  • 1 cup sharp cheddar cheese (shredded)
  • 1/2 cup gruyere cheese (shredded)
  1. Preheat oven to 375°F.
  2. Peel and cube rutabaga. Place in a pot of cold water and bring to a boil. Simmer 10-15 minutes or just until tender. Do not overcook, they will cook more in the oven. Drain well.
  3. Meanwhile, cook onion in butter on medium low heat until translucent, about 5 minutes. Add flour and thyme, cook 2-3 minutes.
  4. Add milk a little bit at a time stirring until smooth after each addition. It will seem thick at first but will smooth out with each addition. Cook over medium heat until thick and bubbly. Remove from heat and stir in cheeses until melted. Season with salt & pepper to taste.
  5. Toss sauce with rutabaga and transfer to a 2qt baking dish. Bake uncovered for 35-40 minutes or until lightly browned.

Close up of a rutabaga gratin casserole.
Close up of a rutabaga gratin casserole.
Top photo - Close up of a rutabaga gratin casserole. Bottom photo - A rutabaga on a cutting board being cubed.