"All of us were looking to get into the restaurant business at the same time," Shackelford said.
"Basically being able to own a place right around where we grew up and went to high school was a big draw to us," the Catonsville resident said. "We knew that right off the bat we would have a pretty good following just from our friends."
In 1996, the trio opened a second GL Shack's in Columbia. It is now known as Lee Lynn's and is independently owned by Stumpf.
After Stumpf took over the Columbia restaurant in 2000, Shackelford and Tolker owned and operated Tiber River Tavern, now Diamondback's, in Ellicott City for four years.
Tolker left the restaurant business to go into sales three years ago. "Now it's just myself here," Shackelford said.
In addition to the Frederick Road restaurant, he also owns a GL Shack's in Eldersburg.
He said he can't believe 20 years have passed since he began the business venture as a 32-year-old and added that he couldn't have gotten to this anniversary without his two original partners.
"In the beginning in 1993, all three of us worked here every day," Shackelford said. "Now that I'm down to basically myself and my staff, I don't think I realistically pictured that [the 20-year anniversary] would happen."
Shackelford said hard work and a good staff have kept his business going through the years.
One of the hard workers on that staff is his 20-year old son, Dylan, who has been working there for five years.
"I've been very fortunate over the years to have a lot of the same employees stay with us for six, eight, 10 years," Shackelford said.
James Upman, the restaurant's full-time executive chef for the past four years, has been working for Shackelford on and off since he was 16 years old.
"I just started off doing a whole bunch of random stuff: bar backing, dishwashing, making salads. Kind of introductory type work," the 30-year-old Catonsville resident said.
"I bounced around probably from 2000 to 2007 or 2008 to different restaurants, the hotel industry," he said. "I worked in fine dining, stuff like that. I just tried more of less to get a free education learning from other chefs."
When Upman decided he wanted something a little more permanent, he returned to GL Shack's.
"I had always planned that this industry would be a career move," Upman said. "I've had a good relationship with Rick for a long time."
Upman is glad to see Shackelford's business doing so well after 20 years.
"Just from a business prospective, for any business owner to have any business for 20 years, you should have a sense of accomplishment," Upman said. "Hopefully, customers and patrons, obviously they're happy, and hopefully we can keep that going for another 20 years."
Randy Shallue and Karl Medinger have been two of those "happy" customers for the past 19 years. They visit for lunch several days a week, they said, drawn by the service and specials.
The men, who work for the same company in Woodlawn, started trying out restaurants for lunch 19 years ago before settling on GL Shack's for the atmosphere and the service.
"They cater to their lunchtime customers," Medinger said. "They use the red light to allow quick service to get people in and out."
The red light is a red light bulb above the bar that is flipped on whenever food is ready in the kitchen or to alert the bartender. The system allows for food to be delivered quicker than in other restaurants, the pair of regulars said.
"It means they take care of their customers," Shallue said.
To celebrate his customers and 20 years of success, Shackelford will host a party at the restaurant on Saturday, Sept. 7. There will be live music in the rear parking lot from 3 to 6 p.m. and a disc jockey inside from 6 p.m. until closing time at 2 a.m.