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Parsnips are a severely underrated vegetable; I’m sure many people just think of them as a white carrot (not true), and I’ve seen them mislabeled at the grocery store on more than one occasion. But don’t overlook them the next time you’re at the farmers market; these unassuming vegetables make this gratin a truly special dish.
Parsnips Bring It In the Flavor Department
Parsnips belong to the same botanical family as carrots, parsley, cilantro, fennel, and celery. Parsnips have a sweet flavor with a mild, earthy undertone, and they have the texture of carrots. In fact, they were once used as a source for sugar, before Europeans cultivated sugar cane and sugar beets.
Parsnips are in season from late fall through winter, making them a perfect, seasonal fit for holiday dishes.
Ingredients and Substitutions
Parsnips
Good substitutes for the parsnips here would be other root vegetables like turnips or rutabagas. Rutabagas have a very strong sulfurous scent when raw, but they do mellow as they are cooked, so I wouldn’t hesitate to use them here. Carrots could also work and would bring some sweetness to the gratin, but they do not have the same earthy flavor as parsnips.
Potatoes
I used russet potatoes in my recipe, but any potato would work well here. Waxy potatoes will hold their shape more (think Yukon Gold or red potatoes) than the starchy russets, but the flavor and overall texture will be very similar. Russet potatoes are quite large; if buying Yukon Gold potatoes, buy more to make up for their smaller size.
You could also use sweet potatoes here. I’d recommend either the Bellevue or the O’Henry sweet potato varieties as a substitute for the potatoes in this gratin.
Heavy Cream
Don’t skimp on the heavy cream! Whole milk won’t be the same here; the fat content of the heavy cream is necessary to balance out the starchiness of the potatoes. It’ll really bring the whole dish together.
Gruyere Cheese
Gruyere is a Swiss alpine cheese that has excellent melting properties, as it’s one of the most popular cheeses for fondue. It’s nutty and creamy, and a perfect match for the parsnips.
If you don’t have gruyere on hand, a sharp white cheddar could be substituted. The cheese flavor will be more prominent, but that’s not necessarily a bad thing.
Tips and Tricks
A mandolin slicer will make slicing the parsnips and potatoes quick and easy, and it will ensure that all of the slices are even in thickness. Make sure that the blade is sharp, and use the hand guard. The parsnips will be slightly tougher to cut than the potatoes, so it may make sense to cut the parsnip in half to get a better grip on the vegetables before slicing.
Don’t worry about getting a pretty pattern with all of the layers of the gratin. Only the top layer will be visible at the end, so as long as you can fit all your parsnips and potatoes in your baking dish, it doesn’t matter if they’re neatly organized or not. I did a very simple layered pattern on top; I can assure you that the layers underneath the top are not so neatly organized.
Serving Suggestions
This parsnip and potato gratin will steal the show of your next dinner party! Serve it with roasted green beans or a simple salad and a protein of your choice. It’ll also work quite well as a main dish for any vegetarians (or, honestly, any cheese lovers out there).
If you have leftovers, slice up the gratin and freeze it in individual portions. It’ll reheat quite well in the toaster oven; leave it uncovered toward the end of reheating so that the top remains crisp and the parmesan cheese on top browns.
Creamy Parsnip Potato Gratin
Don't overlook parsnips the next time you are at the farmers market; these unassuming vegetables bring the flavor in this stunning parsnip potato gratin.
Ingredients
- 1 tbsp avocado oil
- 1 pint heavy cream
- 3 cloves garlic, minced
- ½ tsp salt
- ¼ tsp white pepper
- 3 large parsnips
- 3 russet potatoes
- 1 cup gruyere cheese, shredded
- ½ cup parmesan cheese, finely shredded
Instructions
- Preheat oven to 350°F.
- Grease a 9x13 glass casserole dish using the avocado oil. Make sure the dish is completely coated in the oil.
- Heat the heavy cream in a saucepan until small bubbles begin to form on the sides of the pan. Remove from the heat and add the garlic, salt, and white pepper. Set aside (off the heat) for the garlic to steep in the cream.
- Peel and slice the parsnips and potatoes in ⅛ inch thick rounds. Use a mandolin slicer to ensure even slices.
- Divide the potatoes and parsnips into three even piles. Layer the first third of the potato and parsnip rounds into the bottom of the 9x13 dish. Add ½ cup of the grated gruyere cheese in an even layer on top of the parsnip and potato rounds.
- Add the next third of the parsnip and potato rounds to the dish. Add the rest of the gruyere cheese in an even layer on top of the parsnips and potatoes.
- Add the last third of the parsnip and potato rounds to the dish. This layer will be visible.
- Pour the heavy cream mixture over the parsnips and potatoes. The amount of cream should come up to just under the last layer of parsnips and potatoes.
- Top with the parmesan cheese.
- Cover the dish with aluminum foil and bake for 45 minutes.
- Remove the aluminum foil and continue baking for another 20-30 minutes, or until the parsnips and potatoes are soft and the parmesan cheese on top becomes golden brown.
