by Chef Laura Frankel, author of Jewish Cooking for All Seasons (Wiley) and Jewish Slow Cooker Recipes (Wiley)
I love the flavor of celery root (celeriac). The intense celery flavor and “mashed potatoey” consistency pairs well with the potatoes and roasted garlic. Celeriac is what celery wishes it was. It is crunchy and sweet when raw and soft and creamy when cooked. I insist that you use homemade aioli to fluff your potatoes. Jarred mayonnaise is not a substitute in this case and will not yield great results. Fake milk and butter products are not even part of the discussion. They produce a WET-heavy mash that cannot possibly absorb all the gravy I love. Homemade aioli is fluffier, tastes better and simply makes a better creamy-fluffy mash.
1 whole head of garlic, cut horizontally but not peeled
4 large Russet potatoes, peeled and cut into large dice
1 large celeriac bulb-peeled and cubed
Preheat oven to 400 degrees.
Drizzle a teaspoon of olive oil on the cut sides of garlic. Wrap in foil and place in preheated oven for 1 hour until the garlic is brown and very soft. Set aside to cool.
Bring a large pot of water to the boil. Add the potatoes and celery root. Cook the vegetables until they are very soft but not breaking apart (about 20 minutes). Drain the potatoes and celery root. Return the vegetables back to the pot over low heat. Allow the vegetables to gently dry out in the warm pot over low heat for 3-5 minutes.
Transfer the potatoes and celery root to a large mixing bowl. Squeeze the garlic out of the bulb. Rice the potatoes and celery root and roasted garlic through a potato ricer or use a potato masher. Do not use a mixer as the potatoes will become too starchy.
Add 1/2 cup of aioli* to the riced mixture. Stir to combine. Add additional aioli until you have the texture and fluffiness you like. Season with salt and freshly ground pepper. Garnish with chopped chives, celery leaves and fried sage.
* For the Aioli
Fresh aioli is creamy and rich. A famous chef said that it is “the butter of Provence”! What can I say? Aioli can be stored, covered in the refrigerator for 5 days. I whisk my aioli together by hand just because I enjoy doing it. You can easily use a food processor or blender.
2 egg yolks
1 teaspoon Dijon style mustard
3 teaspoons of water
1 tablespoon fresh lemon juice
1 cup neutral flavored vegetable oil (I use canola)
Salt and pepper to taste
Place egg yolks, mustard, water and lemon juice in a food processor or non-reactive stainless steel mixing bowl or a glass bowl. Pulse or whisk together until smooth. Slowly add oil drop by drop into the bowl while continually whisking or processing. The mixture should resemble mayonnaise. Salt and pepper to taste.