When Mike Cosentino graduated from Upper Darby High School in 1991, he didn't go to college right away. He went to Swiss Farms.

The drive-through-only convenience chain, with 12 stores and a presence limited to Delaware County, was his initiation to full-time employment. Dressed in layers in winter to brace against the cold, Cosentino usually worked the late shift — 4 to 10 p.m. — filling orders from motorists as they pulled up to the sliding doors on either side of the tiny store.

Milk. Bread. Eggs. Bacon. Tastykakes. Soda. Those were the standard purchases at Store No. 4 on Baltimore Pike in Springfield, where Cosentino spent three years, part of them as assistant manager, before pursuing a career that had intrigued him ever since the home-improvement show This Old House captured his attention as a 6-year-old: architecture.

More than 20 years later, that career choice has Cosentino back working for Swiss Farms — this time, to craft a new look for the 49-year-old retail curiosity whose stores are modeled after barns, each with an impossible-to-miss red silo.

The silos aren't going away, but with a revised roofline, skylights, louvers, lighting upgrades, and a more upscale and contemporary look, the redesign is intended to better attract and serve customers, said Scott Simon, president and chief executive of Swiss Farms.

It's a competitive field, in which one of the biggest players — Wawa — also is upping its game in Delaware County with the recent reopening of a Chadds Ford store renovated to include seating and beer sales.

As a retailer whose customers don't get out of their cars, Swiss Farms sees its opportunity to make an impression as fleeting.

"We create a 90-second experience for our customers — like a Disney ride," Simon said.

Created in 1968 by the family-owned Wengert Dairy Farms in Lebanon, Pa.,  Broomall-based Swiss Farms — with 206 employees and an $8.50 average drive-through tab ($30 for orders made online and picked up later) — is owned now by MVP Capital, a private-equity firm in Radnor. The founding Wengert family sold the dairy in 1999 to Dean Foods, a national food and beverage company headquartered in Dallas.

Simon, 56, who would not disclose company revenues, has been with Swiss Farms only since April 2016. Landing an architect for the redesign who has a history with the company was "very serendipitous," he said. "It's all about the circle of life."

For Cosentino, 43, senior partner at Linn Architects in Media, "it was more fun than anything," he said on a recent afternoon, standing amid shelves of snack cakes, chips, and paper towels in the store where the blueprints tucked under his arm will first be applied.

Within Swiss Farms, it's known as Store No. 9, built in 1975 on North Eagle Road in Havertown. That its silo, where the ice machine was housed, blew down in November helped propel it to the top of the makeover list. So did all the sales-interrupting construction around it, including a YMCA and a Mr. Storage, Simon said.

"It will be really cool if I can go back and do Springfield," said a nostalgic Cosentino.

He likely will have that chance, said Simon, if all goes well with the Havertown redo, expected to cost $350,000, begin in mid-March, and finish by the beginning of July. "We hope to do four stores a year."

Given that Swiss Farms customers don't have the option of coming inside and browsing the 750 items available for purchase, which occupy nearly every inch of cooler, counter and shelf space in the 750-square-foot store, Cosentino said better visibility was a redesign priority.

"The biggest thing was getting the products displayed before people get to the door," he said.

The other was to add an e-commerce pick-up lane, so online customers don't have to wait behind those doing their shopping at the doors.

Though a lot has changed at Swiss Farms since Cosentino first worked there — credit cards are accepted, computers track inventory, and food offerings now include fresh, made-to-serve meals prepared in the company's commissary in Milmont Park — the core principle is as it was when the chain started: convenience.

"My wife sends me to the one in Brookhaven all the time," said Cosentino, who lives there. "I drive right by the Wawa to do that. ... The only thing I go to Wawa for is gas."