Tony Muia operates a pizza tour of Brooklyn, but this weekend he says he canceled tours for two days due to a startling and upsetting situation — the murder of Louis Barbati, co-owner of L&B Spumoni Gardens, a destination for tourists and one of the city's most famous pizzerias.

Barbati was shot to death last week outside his home in Dyker Heights, while returning from the restaurant.

On Friday, NYPD Chief of Detectives Robert Boyce called the shooting “possibly a botched robbery attempt,” noting that Barbati was carrying $10,000, cash. But the suspect left the money and Barbati’s jewelry at the scene.

Adding to the lurid details, Barbati’s restaurant was connected to an organized crime feud in a 2012 extortion case: a Colombo family associate related to another co-owner by marriage was accused of threatening a rival pizzeria owner for stealing the recipe for the Spumoni sauce.

Pizza to travel for

The old mob story and the pizzeria’s fame drew attention to a segment of Brooklyn that some say has disappeared. But Spumoni Gardens, founded by Barbati’s grandfather in 1939, is one of many swathes of Brooklyn where little has changed in recent decades.

The pizzeria is a mecca for pizza-lovers. The restaurant has indoor seating, but many wait to get their Sicilian slices (or regular slices, if you’re some kind of monster) from a service window and then consume the pizza in picnic-style outdoor seating.

There are rules, but little ceremony.

A sign on the outdoor eatery’s fence warns against parking motorcycles on the sidewalk. A guy selling knockoff DVDs makes his way through the picnic tables, and actually sells some wares.

The restrooms are around the back of the building, past the parking lot, through a back door and a dark corridor opposite the industrial freezer, a trip that wouldn’t seem out of place in a mobster movie death sequence. Inside the bathroom, graffiti includes the nugget “death to communist scum.”

And the pizza — none of that rarefied, thin crust schlock you find elsewhere in Brooklyn. Spumoni Gardens squares aren't afraid to feature burnt crust, their sauce difficult to describe or forget — a little sugar, a little tang. Crisp on the bottom, gooey on top, messy to eat unless you get a corner or end. Both go quick.

Which Brooklyn is authentic?

This kind of “authentic Brooklyn” has been a draw in recent years. Muia, the tour operator, says when he started the company — “A Slice of Brooklyn” — in 2005, tours drew groups of 12 or less. Now, it’s 38 or more.

Muia calls Spumoni Gardens an “integral part” of growing up in Brooklyn, where he was born and raised. He also runs a tour during the winter to the Dyker Heights Christmas lights, another neighborhood institution.

The pizza tour stops at Grimaldi’s Coal Brick Oven Pizzeria, as well as the Brooklyn Bridge and Coney Island. Tour guides point out scenes from movies like “Annie Hall,” "Saturday Night Fever,” and “Goodfellas” along the way — images from Brooklyn’s sometimes homey but sometimes seedy past.

Cases with organized-crime connections, which this one may or may not turn out to be, are rarer than they once were.

The case of Vincent Asaro, who was indicted in connection with the 1978 Lufthansa heist of "Goodfellas" fame, drew attention for the novelty of the prosecution and the old-time outcome: He got off.

Another pizzeria owner, Mark Iacono of Lucali, was brutally stabbed in 2011 by a suspect with organized crime ties, though Iacono has denied the connection.

Christian Cipollini, a historian of organized crime, says it’s too early to tell whether there’s mob involvement here, though “with mob history anything is possible. Truth is stranger than fiction.”

Police released surveillance video of a suspect in the Barbati case Tuesday, picturing a man in sunglasses, shorts and a sweatshirt walking nonchalantly down the street not long before Barbati’s murder.

Muia says he can’t believe Barbati would have been caught up in organized crime.

He remembered the pizza man behind the counter when Muia was a kid, and later working with him on the tour and TV shows, as Spumoni Gardens’ fame grew. He was a “big, lovable guy,” Muia said. “A teddy bear.” He called him “Lou Lou.”

Muia says he cancelled the tour on Friday and Tuesday, when the restaurant was closed for Barbati’s funeral, out of respect for the family. The tours ran over the weekend while the place was open, though Muia says he didn’t talk about the murder.

On July 4th, at least some visitors already knew. “Crazy,” one said briefly, on the way from the bus. Then he continued past the “no motorcycles” sign, ready for his slice.

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