If you eat out or shop the vegetable stalls, the chances are you've seen it. Kale is often treated like the ugly duckling of the greenery field, ignored by otherwise budget- and health-conscious shoppers.
Actually, the vegetable, a sort of green cabbage, has a long history of fitting into hearty international menus -- not just braised with chopped onions, meat stock and pork fat, Dixie-style -- but as an ideal ingredient for balancing casseroles.
The only preparational trick is cutting out tough stems of the leaves.
Locally grown kale, if you can find it, is usually a better flavor buy than imported. In U. S. markets, it's an early winter star, along with Jerusalem artichokes, celeriac and spaghetti squash, making up a quartet that's distinctive but full of possibilities. Some growers leave the kale plants on the ground until after the first winter snowfall.
In Central Europe, baked kale and potatoes are a tradition. Cold, cooked buttered potatoes are moistened with beaten egg yolks and added to a casserole lined with braised or steamed kale that has been drained. Mustard, Strasberg or Dijon style, and white cheese are a likely addition to such a dish, and nutmeg a likely spice. Sometimes the yolks are replaced by hard-cooked eggs.
Actually, the vegetable has the ability to absorb a wide range of herbs and spices. Some of the candidates, normally added to the cooking liquid, are marjoram, oregano and tarragon, but not necessarily all at once. Kale also has an affinity for modest additions of pepper, added as a finishing touch, either red or black varieties.
Here is a cheese-flavored casserole that uses kale in the company of Parmesan flavoring. It's included in "Fresh Ways with Vegetables" (Time-Life Books) introduced in the 1980s.
Kale gratin with ricotta and Parmesan cheeses
3 pounds of kale, washed with stems removed
1 cup unsalted chicken or vegetable stock
1 onion, chopped
1/2 cup rice
1 tablespoon chopped fresh thyme or 1 teaspoon dried thyme leaves
1/2 cup part-skim ricotta
5 tablespoons freshly grated Parmesan cheese
1/4 teaspoon grated nutmeg
1/4 teaspoon salt
freshly ground black pepper
1/4 cup fresh bread crumbs
1 tablespoon virgin olive oil
Pour the stock into a small saucepan, add the onion and bring the liquid to a boil over high heat. Add the rice and thyme. Reduce the heat to medium low, cover the pan and simmer the rice until it is tender -- about 15 minutes.
Heat the oven to 400 degrees.
Meanwhile, put the kale in a large pot, cover the pot tightly and cook the kale over medium-high heat until it wilts, three to four minutes. (The water clinging to the leaves provides enough moisture). Drain the kale and coarsely chop it. Combine the kale with the rice, ricotta, 1/4 cup of the Parmesan cheese, the nutmeg, salt and pepper.
Put the mixture into a lightly oiled, 1 1/2 -quart gratin dish. Sprinkle on the bread crumbs and the remaining tablespoon of Parmesan cheese. Drizzle the oil over the top and bake in the upper third of the oven until the juices begin bubbling -- about 30 minutes. Remove the gratin from the oven and turn on the broiler. Place the gratin under the broiler about 5 minutes. Serve immediately.