Shares in Chipotle Mexican Grill ( CMG ) have been a long-term market beater, but there's a twist. The fast-casual food chain is a great example of what happens when a company's days of hyperfast growth have long passed. Like McDonald's ( MCD ), CMG claims humble origins, starting with a single location. The first Chipotle opened in Denver in 1993 and it quickly became a hit. Founder Steve Ellis's focus on high-quality and fresh ingredients served in a fast-food format was revolutionary at the time. The fast-casual restaurant concept was born. From just $107.88 $24.99 for Kiplinger Personal Finance Become a smarter, better informed investor. Subscribe from just $107.88 $24.99, plus get up to 4 Special Issues CLICK FOR FREE ISSUE Sign up for Kiplinger’s Free Newsletters Profit and prosper with the best of expert advice on investing, taxes, retirement, personal finance and more - straight to your e-mail. Profit and prosper with the best of expert advice - straight to your e-mail.…