What happens when you give a bunch of Boston architects some gingerbread?

They are tasks in tedium, exercises in OCD, bits of eatable holiday humdrum.

Yes, the State House’s 23-carat gold leaf dome is edible. Yes, those are stained sugar glass windows in the Old North Church.

Architects, after all, love detail. Hence, this year’s iteration of the Boston Society of Architects (BSA) gingerbread house competition, which has been on public display at 290 Congress St. for the past two weeks.

Lexington’s Connor Architecture, for instance, took 40 hours to build a miniature State House. Bits of chocolate masonry are a sweet stand-in for the stone steps of the real thing. Then there’s the structure’s iconic golden dome.

“We are insane enough to source it from a pastry chef in New York,” said Charlotte Connor. “It took us by surprise, how fun it was and how fierce the competition was.”

She added, “Architects can be a little crazy.”

STV Group Inc., known locally for transportation projects, recreated the Longfellow Bridge, also known as “salt and pepper shaker bridge” because of the shape of its towers. Most of the firm’s 92-strong Boston office have worked on a design build project for the real thing, which connects Kendall Square and Beacon Hill, across the Charles River.

The group initially struggled to make everything edible, but ultimately decided, “Anything is edible if you set your mind to it.” The end result features rice crispy treats for the piers and towers, gingerbread and frosting for the granite façade and a chocolate syrup and Oreo crumb roadway.

“One of the challenges was discovering how to make it small enough to meet the design criteria, yet big enough to have it be detailed,” said Kristine Gorman, an STV project manager.

Finegold Alexander + Associates, based in the North End and known for its work on the Hatch Memorial Shell, Old City Hall in Boston, the Vermont State House and the Ellis Island National Monument, recreated the Old North Church

The structure is the oldest standing church in the city, perhaps best known for its link to Paul Revere’s midnight ride – it is thought to be where the “one if by land, two if by sea” signal was sent.

Finegold Alexander, which won the competition last year with its candied rendering of the Hatch Shell, put a Necco finish on the roof, used stained sugar glass for the window and created the steeple from gingerbread, fondant and a deconstructed ice cream cone for the spire. A team of four spent three nights making the piece.

“We couldn’t leave out some Italian inspirations so the fence and the light posts are made with spaghetti,” said Josephine Penta, an architect with the firm.

Competitors seek donations from fans of their work, and The team with the most donations is declared the winner of the competition. All proceeds from the competition benefit the Community Design Resource Center, which provides pro bono design and technical assistance for nonprofits and projects for underserved communities in greater Boston.

As of press time, a bidding war was said to be on between Finegold Alexander’s Old North Church and Connor Architecture’s State House, according to Boston Society of Architects.