This build-your-own sandwich includes pastrami, mortadella, mozzarella, giardiniera and sauerkraut on marble rye bread at Broadway Delicatessen in downtown San Antonio.

Broadway Delicatessen opened in September in downtown San Antonio, offering sandwiches, hot dogs, pizza and salads.

Broadway Delicatessen opened in September in downtown San Antonio, offering sandwiches, hot dogs, pizza and salads.

The menu at Broadway Delicatessen

The menu at Broadway Delicatessen

In a previous life, the home of Broadway Delicatessen was a jewelry store, in case you couldn’t tell from the black marble casements around the windows and the blue neon Gildemeister’s marquee hanging in the dining room.

The downtown building at 122 Broadway sells a different kind of gem these days: deli sandwiches inspired by owner Arnold Mendoza’s travels through the upper East Coast in his 20s, hitting the classic delis of New York and the surrounding region.

Like the shop he runs now, the San Antonio native’s lived a few past lives of his own, working as a FEMA contractor and running the late Bunz, Burgerz & More in Southtown and the Groove Lounge bar just east of downtown.

Broadway Delicatessen owner Arnold Mendoza holds his shop’s Boston sandwich with capicola, pepperoni, Canadian bacon, provolone cheese and red vinaigrette.

But Mendoza’s time on the East Coast cultivated the passion that drove him to open Broadway in September.

“My goal is to educate people on corned beef, pastrami and Italian beef,” he said, a goal fostered by a menu of regionally named sandwiches and a build-your-own-sandwich roster of meats, breads, cheeses and spreads with permutation possibilities ranging into the thousands.

In a shop that encourages people to create their own masterpieces, what’s Mendoza’s go-to sandwich? “I’m a corned beef and pastrami guy,” he said.

And really, aren’t we all?

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Menu options at Broadway Delicatessen in downtown San Antonio include, clockwise from bottom left, a build-your-own pastrami and mortadella sandwich, a Cleveland sandwich, a Boston sandwich, a Jersey City sandwich, a Los Angeles sandwich and a Waldorf salad.

Best sandwich: This clean, casual shop a block away from Travis Park also offers hot dogs, salads, soups and pizzas hand-tossed by Mendoza’s “right-hand guy” Chris Don, who multitasks as a good sounding board for the build-your-own sandwich adventure.

Thanks to him, I felt comfortable combining the high-voltage twang of sauerkraut with the spicy, escabeche-style bite of giardiniera on a sandwich piled with a half-pound of razor-thin pastrami, a half-pound of old-school slick mortadella, melted mozzarella and spicy mustard on marble rye ($12.98) — like a school-lunch brown bag if your mom worked at a deli. It was a decadent and hefty mix of salt, fat, tang, spice and satisfaction.

The Los Angeles sandwich incorporates ham, turkey, bacon, provolone cheese, guacamole, cucumbers and jalapeño mayo on wheat bread at Broadway Delicatessen in downtown San Antonio.

Other sandwiches: Mendoza was hesitant to admit that Broadway’s best-selling sandwich falls far west of the East Coast, a compilation called the Los Angeles ($11.99), built on toasted wheat bread with ham, turkey, bacon, provolone cheese, cucumbers, guacamole and jalapeño mayo.

L.A. in S.A.? No way. But think about it: Those last two ingredients — guacamole and jalapeño mayo — are every bit as South Texas as they are West Coast. So really, this was like a San Antonio club sandwich, a club where we’re already members.

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The Jersey City sandwich comes with Italian beef, giardiniera and provolone cheese on an Italian roll with beef jus on the side at Broadway Delicatessen in downtown San Antonio.

A trio of sandwiches paid tribute to the Midwest and New England, starting with the Jersey City ($9.99), a variation on a Chicago beef dressed out with shaved roast beef and melted provolone cheese with a side of salty beef jus for dunking. Generations of Chicagoans would testify that that’s all you need, but the Jersey City added giardiniera for sour-spicy street cred.

The Boston sandwich ($11.99) got more fussy, with a three-meat layering of capicola, pepperoni and Canadian bacon with provolone on a chewy Italian roll. The fussy part came from lettuce, tomatoes, onions, olives and red vinaigrette dressing that, taken as a whole, made it more like eating a salad than a proper Italian deli sandwich.

The Cleveland sandwich comes with corned beef, Swiss cheese and Russian dressing on sourdough bread at Broadway Delicatessen in downtown San Antonio.

Leave it to Cleveland ($9.99) to bring things back into balance with a blue-collar buildout of corned beef sliced thin and piled high on sourdough with melted Swiss cheese and Russian dressing with a horseradish kick that said through gritted teeth, “I dare you to call me Thousand Island. One. More. Time.”

msutter@express-news.net | Twitter: @fedmanwalking | Instagram: @fedmanwalking

Location: 122 Broadway, 210-455-8388, broadwaydelisa.com

Hours: 11 a.m.-8 p.m. Monday-Friday; noon-9 p.m. Saturday

Mike Sutter is the Express-News restaurant critic. Before joining the Taste Team in 2016, he served as restaurant critic for the Austin American-Statesman and editor of FedManWalking.com. He's appeared on NPR's "All Things Considered," ABC's "To Tell the Truth" and written for The Guardian, Bon Appetit and The Wall Street Journal.