In the beginning, breakfast cereal was just that: raw cereal grains such as oats and wheat that had been rolled or flaked or shredded to make them easier to eat, usually with milk. Then came the puffing and the extruding, the syrups and the dyes, the animal shapes and the cartoon mascots who beckoned us to the table, and we heeded their call. Today, ready-to-eat cereal is the most popular morning meal in the United States, edging out bread itself. Many of us may go for the Kashi GoLean Crunch over the Count Chocula these days, but it's hard not to marvel at how far this food has traveled from its roots. Those nostalgic for more-innocent times would do well to look to the Swiss, for whom a simple breakfast of raw cereal flakes, fruit, nuts, and yogurt or cream constitutes a near-sacred daily rite.

Muesli, as that delicious, high-fiber food is called, was introduced to the world by Maximilian Bircher-Benner, a Swiss medical doctor and dietary reformer who arguably made a more enduring contribution to healthful breakfasting than his better-known American contemporary John Harvey Kellogg. Around 1904, Bircher-Benner began serving the patients at his Vital Force sanitarium in Zurich a mixture of rolled oats, grated apples, ground hazelnuts and almonds, and condensed milk. He named the dish muesli—literally, little mush. Although no one these days eats Granose, the flaked-wheat breakfast food created by Dr. Kellogg in the late 1800s, or his original Granola, a graham-flour-based precursor to today's granola, the original Bircher-style muesli is still served across Switzerland.

Although that's true, many Swiss don't make muesli the Bircher-Benner way at home anymore, preferring sweeter, crunchier versions flavored with everything from vanilla to flaxseeds to fresh and dried fruit. And packaged muesli, the dry mix to which milk or yogurt is added before it's eaten, has proliferated across Europe: a German company called Mymuesli will custom-mix raw cereals, nuts, fruits, and extras (from holiday spices to Gummi bears) and ship the ingredients to customers in a Pringles-style canister. Even Bio-familia, the venerated Swiss cereal maker that first packaged a Bircher-style muesli, in 1959, now makes more than 150 varieties using hundreds of different ingredients.

And yet, when I paid a visit to Hans-Peter Binz, the 63-year-old president and CEO of Bio-familia, at the company's factory in central Switzerland, it was old-fashioned "birchermuesli" that he was the most eager to talk about. "Dr. Bircher-Benner did not invent muesli," said Binz, dressed in a crisp beige suit and perfectly knotted tie, as we sat in his office overlooking a mountain lake. "He saw people living in the Alps eating oats mixed with raisins, apples, maybe nuts, and he adapted the recipe. Real muesli is the one true Swiss food."

That echoed a sentiment I'd heard from other Swiss people. Eberhard Wolff, a cultural historian at the University of Zurich with whom I'd had lunch a few days earlier, described muesli to me as nothing less than "the essence of Swissness": uncomplicated, salubrious, rustic yet sophisticated. That essence has acquired a 21st-century aura at the Zurich Development Center, the corporate conference facility and retreat that has taken over the grounds of Bircher-Benner's former clinic, parts of which the center has preserved for posterity. I visited the place on a rainy morning and was shown around by a slim woman in a gray pantsuit named Ursula Muri. Ushering me in by way of whisper-quiet automatic sliding doors, she showed me Bircher-Benner's old library as well as a "wellness center" (a gym), lush gardens, and a two-lane bowling alley. She invited me to the restaurant, where true Bircher-style muesli, made with condensed milk and grated apples, is served every morning. I sat down with a bowl of the cereal, clean tasting and bursting with the flavor of tart apples, and wondered whether Americans, too, might eventually come to think of muesli not as a health food but simply as good eating.