Pile 'em high! A Dagwood is considered by many the epitome of what a sandwich should aspire to. Photo: Universal Studios.

In between the extremes of the artisanal breads of Panera Bread (NASDAQ:PNRA.DL) and some local deli's gravity-defying Dagwood-style sandwich stacked with multiple layers of cold cuts, cheese, and condiments, today's hungry diner has a seemingly limitless choice of places to grab a sandwich or sub.

We've entered a golden age of sandwich-making, and though the more wholesome, fresh ingredients used by trendy fast-casual chains such as Panera grab most of the headlines, consumers seem to prefer simpler options when determining what makes for good-tasting food.

Which is probably why Panera Bread did not score particularly highly among sandwich or sub chains in a survey of more than 32,400 Consumer Reports subscribers who ranked 65 restaurants during 96,000 dining experiences across the country. It came in at No. 7 of the 15 chains in the survey.

Hot doggin' it
Some other well-known restaurants also fared poorly, including ninth-place Potbelly (NASDAQ:PBPB), and 10th-place Quiznos. And despite being viewed as offering customers the healthiest food options, Subway ranked second to last when it came to taste.

So which chain topped the best-tasting list? None other than Chicago's Portillo's Hot Dogs.

Source: Consumer Reports "America's Best & Worst Food."

While named for hot dogs, Portillo's is also known for its italian beef and chicken sandwiches. 

From lowly beginnings, an empire
Portillo's has beginnings as humble as the hot dog itself. The first Portillo's Hot Dogs wasn't even a storefront, but rather a 6-foot by 12-foot trailer in Villa Park, Ill., that was called "The Dog House."

After gaining a level of success, it was rechristened Portillo's and expanded in and around the Chicago area. Nothing says America more than baseball, hot dogs, and apple pie, so perhaps it's fitting a hot dog stand in the Windy City heads the pack of top sandwich and sub shops. Few cities outside of Chicago are more closely associated with baseball, and the town is almost synonymous with hot dogs. Chicago red hots, anyone? The chain's 45 restaurants can now also be found in Southern California, Arizona, and Indiana.

Despite Portillo's parochial nature, it has an international reputation, and receives orders from as far away as Europe and China. The chain says on its website that it won so many Silver Platter awards -- sort of like the Oscars for the food industry -- that it withdrew from competition for five years just "to give others a chance."

Portillo's menu features burgers; chicken, fish, and veggie sandwiches; and even salads. But its claim to fame, and what gets customers clamoring and coming back for more, are its hot dogs, specifically the classic Chicago-style hot dog.

You don't mess with the original
The Chicago dog is a Vienna Beef hot dog, wrapped in a steamed poppy seed bun, and topped with mustard, relish, chopped onions, sliced tomatoes, a kosher dill pickle spear, and "sport peppers."

The classic Portillo's Chicago-style hot dog. Photo: Juan-Calderon via Flickr.

One other thing that separates Portillo's from its rivals is a willingness to put ketchup on its hot dogs, a decided no-no among aficionados. Also, each Portillo's restaurant reflects a different theme. Depending upon where you dine, you could be sitting in a 1920s-, 1930s-, 1950s-, or 1960s-themed restaurant.

An American favorite
Whether you call them tube steaks, Coneys, dirty water dogs, or red hots, the hot dog remains an iconic American food. Hebrew National is one of global food giant ConAgra's (NYSE:CAG) most significant brand names; Oscar Mayer from Kraft Foods (UNKNOWN:KRFT.DL) generates over $1 billion annually in sales; and Nathan's Famous (NASDAQ:NATH) generated over $65 million in sales last year, a 15% increase from 2013.

But Portillo's might soon grow even larger. Last summer, company founder Dick Portillo sold his chain of hot dog restaurants to private equity firm Berkshire Partners for an estimated $1 billion, and included Portillo's Restaurant Group's other concepts, Barnelli's Pasta Bowl, Luigi's House, and Honey-Jam Cafe. The company operated generated some $300 million in revenue last year.

While, as with laws and sausages, you probably don't want to see hot dogs being made, the slender wiener will remain indelibly marked as an all-time American favorite in ways new dining trends will never match.