Friday, March 11, 2011

Celeriac and Potato Purée

Many of the vegetables of winter (turnips, parsnips, cabbage, Brussels sprouts, cauliflower,...) carry with them the baggage of a poor reputation. People who haven't tasted them seem to be certain that they won't like them. Since I think all of the ill feeling towards these vegetables is undeserved—most likely the product of poor cooking—I always try to tuck in a couple of classes during the winter months that feature these vegetables so that people can taste how very good they can be. This year I included celery root (also called celeriac) in two of those classes. Celery root (literally the root of a type of celery that is bred to produce a large root and an insignificant bunch of celery) doesn't suffer from quite the same problem as the other vegetables I have listed. More often than not, people have never heard of it. Even if they have, they seem to want to lump it with the rest of the winter vegetables that they think they don't like.

Celery root's lack of popularity (at least in the U.S.—it is well-loved in France) isn't helped by its appearance. It really is an unpromising looking vegetable. It is bumpy and gnarled and there is always gritty soil embedded in the crevices of the root. If it has not been trimmed before being placed in the produce bin it is crowned with what appears to be a stunted head of celery. It is not something someone would look at and immediately think about tasting. It is a bit like the artichoke in that it makes you wonder about the brave soul who first decided to put it in their mouth. Celery root tastes like celery, but it is not nearly as strong. Upon tasting it for the first time you are aware that it reminds you of something else...and then you realize that that something else is celery, only you didn't remember liking celery quite so well.

Celery root is a versatile vegetable. It can be eaten raw. (The classic salad Celery Root Rémoulade is nothing more than raw celery root, julienned and tossed with a mustardy mayonnaise.) When cooked, it is good in soups, vegetable ragouts, gratins, and purées. Like most root vegetables it is excellent roasted. I particularly like to combine it with other root vegetables (especially potatoes), apples, wild rice and mushrooms. It makes a good partner for pork or chicken or beef. It's flavor is enhanced by parsley, thyme, mustard, olive oil, butter and cream.

When purchasing celery root, choose one that is heavy for its size and firm. If a celery root is much larger than a pound or a pound and a half, it is likely that it will be fibrous and tough. So look for one that weighs about 3/4 to 1 pound. If not using it right away when you get it home, trim away the green and store in a plastic bag in the vegetable crisper. Celery root keeps well. I have never had one hang around long enough to go bad. Deborah Madison says that when stored as described it will keep "several weeks."   When you are ready to use it, trim away  the tough exterior to expose the pale green-ish white flesh:

 If you have never tasted celery root before, I have the perfect recipe for you to try—celery root mashed potatoes. Everyone loves mashed potatoes, which makes this recipe a good place to start. There is nothing unusual about this dish—it appears on restaurant menus and in food magazines with regularity. The reason I want to post it is because I ran across a slightly different way of preparing it in Alice Waters book The Art of Simple Food. I have always made celery root and potato purée by boiling the celery root before puréeing it and adding it to a batch of mashed potatoes. The drawback with this method is that celery root can absorb a lot of water as it cooks to tenderness and the resulting purée has a watered down flavor.

In Waters' recipe, instead of being boiled, the celery root is cooked in some butter, tightly covered, over very low heat, until it is very tender. The process is basically something that Madeleine Kamman calls the étuvée method—"vegetables cooked covered, in their own juices, without any liquid added or, if any, very little". This method is of course the perfect one to use if you don't want a lot of liquid to remain after a vegetable is cooked. It is generally young tender vegetables that are cooked this way since they naturally contain a fair amount of water. Older vegetables that are more fibrous and have lost some of their natural moisture usually need the addition of some water to get them going. (I cook carrots this way when I want to make them into a purée.) If the vegetable you are cooking needs some extra liquid, simply add it. When the vegetables are tender, uncover them, increase the heat and cook until the liquid has evaporated and the vegetables are sizzling in the butter. Celery root, as found at the grocery store, is generally neither young, nor tender. Waters' trick of slicing it thinly to facilitate the cooking process is very clever—no additional liquid is necessary.

The cooked celery root can be puréed a number of ways. It could be passed through a food mill, which will result in a purée with a bit of texture.  I'm not fond of this method, although it is the best method for making potato purée.

Potatoes that have been passed through the medium disc of the food mill

The cooked celery root could also be puréed in the food processor—and this will produce a more refined purée.

Celery Root in the food processor

But my favorite way to purée the cooked celery root is in the blender.  You will have to add some hot milk to get the purée going,

Celery Root pureed with milk in the blender

but the resulting purée will be incredibly silky.

Celery root pureed in the blender with milk

Celery root purée freezes well. The potatoes, however, do not. But if you like the celery root and potato purée, you can make up a big batch of the celery root purée and freeze it in portions you are likely to use. Then on a night when you want to enjoy the special treat of celery root mashed potatoes instead of plain mashed potatoes, you can thaw it, heat it through and add it to your potato purée.

Celery Root Mashed Potatoes would make a great accompaniment to a sautéed chicken breast, or maybe some braised beef short ribs. I served it recently with some roasted carrots and the Mustard Glazed Pork Chop with Apples that I posted in October. Once you try it—however you serve it—I think this surprising little root vegetable will have gained another fan.

Celery Root and Potato Purée

3 T. unsalted butter
1 medium celery root—about 3/4 to 1 lb., peeled, halved and thinly sliced
Whole milk (about 1/2 to 2/3 cup), gently warmed until steaming hot
1 lb. potatoes (Yukon Gold, Yellow Finn or Idaho Russets), peeled and cut into large chunks
2 T. unsalted butter, room temperature

In a wide, heavy-bottomed saucepan, melt 3 T. butter over medium-low heat. Add the celery root along with a pinch of salt and toss to coat the celery root in the butter.

Cover tightly and cook until quite soft—about 12 to 15 minutes—stirring now and then. Lower the heat if the celery root starts to brown.

Purée in the blender or food processor. The blender will give a more silky purée, but you will need to add milk as you blend.

While the celery root cooks, place the potatoes in a saucepan and cover with salted water. Bring to a boil, reduce the heat and cook at a gentle simmer until just tender. Drain. Pass through a ricer or food mill and return to the pot. Fold in 2 T. of butter and the reserved celery root purée.

Adjust the consistency of the purée with warm milk. Season to taste with salt & pepper. Serves 4.

(Recipe from The Art of Simple Food by Alice Waters)

Printable Version


Dee said...

I enjoy pureed celery root without the added potato. Great, tasty low-carb option to have instead of mashed potatoes!

Paige said...

Hi Dee,
Thanks for commenting. Yes, celery root is delicious on its own...but I love it with the potatoes too. And, mixed with the potatoes it's a great way to get someone who might not eat it otherwise to give it a try.

The Omnivore said...

That cooking method is such a great suggestion, thanks! Will definitely keep it in mind. I've been putting ghee into my vegetable purees instead of butter lately -- it's delightfully rich and decadent.