The lines may not be any longer at Chipotle Mexican Grill (CMG -1.34%) than they were a week ago, but at least one Wall Street pro sees some more lettuce in the chain's future. 

SunTrust Robinson Humphrey analyst Jake Bartlett initiated coverage of several restaurant chains on Thursday. Only a little more than half of the calls are bullish, but Chipotle is one of them. His buy rating comes with a $850 price target, suggesting 18% upside from yesterday's close. 

The bullish boost comes at a time when it seems as if growth is slowing at the cult fave burrito roller. Chipotle ended a streak of five consecutive quarters of double-digit growth in comps in the second quarter when comps clocked in at a historically pedestrian 4.3%. Analysts see year-over-year comps continuing to decelerate for the third quarter that concluded last week. Even the upbeat Bartlett is targeting comps of just 2.5% when Chipotle reports on Oct. 20.

This isn't as bad you might think. A major catalyst for the hearty comps Chipotle was posting last year was a major price hike that kicked in during the springtime of last year. It was the chain's biggest menu board increase in three years, done primarily in response to escalating food costs. Now that we've lapped the price hike, it's not a surprise to see comps stabilize.

Bartlett sees comps accelerating to a 5.5% clip for all of 2016, possibly rising back into the double digits come 2017. The end of the carnitas shortage should help smoke braised pork lovers back to Chipotle, and an improving economy should bode well for Chipotle as a popular lunchtime spot, or a place to grab dinner on the way back from work. Bartlett also sees greater traction for its catering and mobile ordering initiatives, something that should help increase sales at the individual restaurant level.

There's also a story developing at Chipotle outside of its namesake chain. It's been a few years since Chipotle opened its first ShopHouse in Washington, D.C., and acquired Colorado's Pizzeria Locale to dive into the fast-growing fast casual pizza market. The time is right to expand both concepts into new territories, and that's something that could ease fears of what Chipotle will do once its Mexican concept saturates the market. 

Bartlett also sees margins improving in the future, with inflation in check and commodities holding up. Chipotle had warned earlier this year that rising beef prices could result in another increase for its steak and barbacoa proteins, but things appear to be stabilizing there. 

As long as Oct. 20's report doesn't offer any unwelcome surprises on either the costs end or the comps front, it may not be long before Chipotle takes out the new $850 price target.