Meal is welcome in the wee hours

WINTHROP -- Never let it be said that Swedes don't know how to have a good time. While they enjoy breakfast, lunch, and dinner, they have also designated a separate meal category, called vickning, for foods that might be consumed late at night -- past midnight, at least -- after an evening spent partying.

"It serves the purpose of breakfast," says Anders Nilsson, standing in his kitchen here, preparing a traditional dish that could serve as part of a vickning. His biff Rydberg, a kind of upscale hash made with lots of butter and bound with a raw egg yolk, could certainly fuel revelers for several more hours, especially when accompanied, as Nilsson suggests, by a shot of aquavit straight from the freezer. The dish takes its name from the former Hotel Rydberg in Stockholm, where it was served.

Nilsson, 47, a mortgage consultant, dons a white chef's jacket and moves with assurance around the stunning kitchen of this ocean-view Victorian. He renovated the space three years ago, and it is designed for a serious cook, with professional-grade appliances, two sinks, ample storage for his oversize pots and pans, and a pantry that, in the Swedish style, vents to the outdoors for cool storage in winter.

His culinary repertoire is by no means limited to Swedish dishes. "I'm just as happy cooking Chinese or Thai food," he says. He speaks of his native cuisine with a sort of fond disparagement. "I think typical Swedish ethnic food is things no Swedes would want to eat," and he notes that in Sweden, traditional food seems to be disappearing, as more cosmopolitan influences hold sway. On his most recent visit to Stockholm, he says, he saw sushi there for the first time.

Nilsson, by contrast, was raised on simple, traditional food. Growing up in a suburb of Goteborg, he learned his earliest cooking lessons from his mother. "I think I was barely 3 when I started helping my mom out in the kitchen; I took an immediate interest in cooking and baking." His mother prepared herring with spirit vinegar, water, sugar, red onions, carrots, and seasonings; she called it simply "herring of the house," he says. After leaving home at 18, he worked in the restaurant business, though not as a cook, traveled, and developed more wide-ranging tastes. He came to the United States to study in 1983 and decided it matched his personality and ambitions.

But if Nilsson has come a long way from Sweden, biff Rydberg brings him right back. To prepare it at home isn't difficult, but there are a few tricks to it. Onions, potatoes, and beef are sauteed separately in butter, arrayed in three mounds or strips on a serving plate, topped with a raw egg yolk, and accompanied by a mustard cream sauce. As with any simple dish, success depends on using quality ingredients. Nilsson carefully cuts the potatoes and onions into tiny, neat dice; he uses a pricey tenderloin, methodically cubed. "You could use a rib eye," he allows, "but then it's just hash." The potatoes are cooked on low heat, which he gradually raises to add a touch of color. "The secret," says Nilsson, turning the potatoes gently as they cook, "is plenty of butter. If I see a dry spot, I add more." Crucial, too, is searing the meat in a hot pan that's large enough to hold it with room to spare; too small a pan, he says, and you'll be boiling the meat rather than sauteing it.

When the three basic components are ready, each diner is served a plateful, with a raw egg yolk cradled in a half shell perched on top. You can eat each part separately, or, as Nilsson prefers, mix it together. As he puts it, "You make a hash of it." The egg adds viscosity and binds the parts together, and it's easy to see how this would be a welcome dish in the wee hours. It's soothing, yet luxurious, rich but simple. And that richness, says Nilsson, serves a useful purpose.

"It's fatty," he says. "It lines your stomach, so you can drink more."

Serves 4

1/2	cup Dijon mustard
1/4	cup creme fraiche
8	tablespoons unsalted butter, or more as needed
2	large onions, cut into 1/4-inch dice
1 1/4	pounds Yukon Gold potatoes, peeled and cut into 1/4-inch cubes
	Salt and pepper, to taste
1 1/2	pounds beef tenderloin, cut into 1-inch cubes
4	eggs
2	tablespoons chopped fresh parsley (for garnish)

1. In a bowl, combine the mustard and creme fraiche; stir well. Refrigerate until ready to use.

2. In a medium skillet over medium-low heat, melt 2 tablespoons of the butter. Add the onions and cook, stirring occasionally, for 10 minutes or until softened and golden.

3. In a second larger skillet, heat 4 tablespoons butter over medium-low heat. Add the potatoes, salt, and pepper. Spread the potatoes into a single layer and lower the heat to low. Cook, stirring occasionally, until potatoes are cooked through, gradually raising the heat to medium-low so the potatoes color a little.

4. When the potatoes and onions are nearly ready, set the oven at its lowest setting (about 200 degrees). Heat another large skillet over high heat. Add the remaining 2 tablespoons butter. Add the meat in batches. Cook, stirring often, until pink inside, and cooked through. Keep the cooked meat warm in the oven until all the meat is ready.

5. On each of 4 plates, arrange some of the potatoes, onions, and beef in separate mounds. Crack an egg, separate the white and reserve it for another use, and place the yolk in half the eggshell on the plate, setting it in the food so it doesn't slip. Serve with the mustard cream sauce. Adapted from Anders Nilsson