Deca Restaurant + Bar's "Zillion Dollar Grilled Cheese," priced at $100 and featuring gold-infused cheddar, celebrates National Grilled Cheese Month. View Full Caption Huge Galdones

STREETERVILLE — The Ritz-Carlton Hotel's restaurant and bar, deca, is offering a limited-edition menu item this month that befits the hotel's ritzy reputation: the "Zillion Dollar Grilled Cheese," a $100 sandwich that features gold-plated 40-year-old cheddar.

The Zillion Dollar Grilled Cheese sandwich, available at the restaurant at 160 E. Pearson St, is made with artisanal sourdough bread coated with Laudemio Marchesi de’ Frescobaldi extra-virgin olive oil, which retails for more than $30 a bottle.

Layered inside the sandwich is thinly-sliced black Iberco ham from free-roaming, acorn-fed pigs raised in the South of Spain. The meat is salted and air-dried for six weeks, then cured for a minimum of 12 months — usually closer to 18 months, said Eric Ciechna, a host at the restaurant.

"Up until a few years ago, you could not get Iberco ham in the United States," Ciechna said. "It's so insanely expensive. We get it in very small quantities."

Most important is the cheese: a 40-year-old aged Wisconsin cheddar infused with 24-carat gold flakes.

Other ingredients include heirloom tomatoes from the Ellis Family Farm in Benton Harbor, Mich., Hudson Valley Foie Gras, which costs about $60 per pound, and a sunny-side-up duck egg.

Dressing the epic sandwich is a drizzle each of a 100-year-old aged balsamic vinegar and Oregon Perigord white truffle aioli.

"Looking at how ridiculously extravagant some of these items are, $100 might actually be a steal on this thing, since there are so many different components to this," Ciechna said.

The sandwich will be available for all of April at the restaurant, which happens to be National Grilled Cheese Month. It comes with a side skillet of lobster macaroni and cheese.

For more information and reservations, call deca at (312) 573-5160.