"Be careful," warns my waiter, sliding a large crouton dish into place on the table—a coating of richly browned cheese toasted into a steaming moonscape across the top, a slight hissing sound emanating from beneath the cheesy crust. "It's still bubbling a little," he cautions, "so proceed carefully."

At Sebastopol's K&L Bistro, a large blackboard on the wall features a pertinent quote from the late Julia Child: "You don't have to cook fancy or complicated masterpieces—just good food from fresh ingredients." It's the perfect motto to ponder as I wait for my macaroni and cheese to cool a bit.

Macaroni and cheese is the reigning king of comfort foods. Among the oldest and simplest dishes ever devised, it has in the past decade established itself as a coveted culinary staple at even the most elegant eateries. Often referred to simply as mac 'n' cheese (the British use the conjunction-free term "macaroni cheese," and the Caribbeans have named it macaroni pie), the enduring entr–e emerged several years ago as part of a recession-era rediscovery of classic home-style recipes. Initially, it was dismissed—along with meatloaf sandwiches—as a mere fad.

Mac 'n' cheese, however, has hardly faded away.

Today, there are countless cookbooks packed with imaginative variations on the theme of pasta and cheesy comestibles. Just across the bay in Oakland, a little eatery named Homeroom recently opened with a menu based entirely on macaroni and cheese. Meanwhile, many of the best restaurants in the North Bay have continued to offer this quintessentially American dish, due largely to popular demand.

The ever-inventive culinary king Mark Stark (Willi's Wine Bar, Stark's Steakhouse and others) offers rotating variations of mac 'n' cheese at his restaurants, including the addictively unexpected Cambozola macaroni and cheese, rich and tangy and irresistible. Though hardly the first restaurant to serve truffled macaroni and cheese, Franco's Ristorante in downtown Santa Rosa has earned fans since adding the dish to its menu. All proof that macaroni and cheese, with or without truffles, is here to stay.

"We serve a lot of macaroni and cheese," laughs Lucas Martin, the L at K&L Bistro (wife Karen completes the equation). "For 10 years, it's been one of our big hits." Martin is amused that a dish many have dismissed as too unsophisticated for culinary-savvy adults has continued to hold its own on a menu that includes things like grilled wild steelhead salmon served with potato pur–e, spinach, green onions and chili flakes. "I find it interesting," he says, "that so many people order the macaroni and cheese for their kids, and then end up eating it themselves. People forget how decadent a dish it can be."

K&L's recipe is nice and simple: begin with a basic flour-and-butter roux, then add a thick and creamy mix of heavy cream and milk in a one-to-three ratio. This is poured into a crouton of preboiled macaroni and plenty of Gruyere and Swiss cheese, and baked until the crust is irresistibly brown and crunchy.

"We've got it dialed in by now," says Martin. "Sometimes people go to extremes, adding all kinds of stuff to the macaroni and cheese. We keep it simple. There are certain things you don't mess with."

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