A lot has happened since Scott Jennings opened his first Cheba Hut, a marijuana-themed sub shop, in 1998. What was still pretty daring has become more mainstream, culturally speaking, Jennings said. And what started as one shop in Tempe, Ariz., where Jennings attended Arizona State University, is turning into an enterprise whose goal is to double in size to 50 restaurants in a couple of years and reach 200 by 2025. Three more of the sandwich shops are set to open in Colorado this year — Denver’s Stapleton neighborhood, Johnstown and Colorado Springs — boosting the total to 12 in the state. Cheba Hut Toasted Subs, now based in Fort Collins, plans to open its 25th restaurant in Las Vegas. “We have several more in the hopper,” Jennings said. There are plans to open franchises in Atlanta, Austin, Texas, and Riverside, Calif.