While many growth stocks have suffered in 2021, one surprising name from the group hasn't skipped a beat: Chipotle (CMG 0.74%). Shares are up 36% year to date and 55% over the past twelve months.

While it's tempting to automatically assume there's no upside left for a stock that has risen so much in such a short period of time, this surface-level conclusion is likely wrong. In this case, the stock's soaring price is evidence of the company's incredible execution. In fact, it's possible that the market has yet to fully appreciate Chipotle's business momentum.

Here's exactly why Chipotle is a stock investors should consider buying today.

A person analyzing charts on a smartphone and a tablet.

Image source: Getty Images.

Rapid growth

The fast-casual burrito maker's recent momentum is impressive by just about every measure.

Benefitting from an easy comparison in the year-ago quarter when the company was negatively impacted by COVID-19 lockdowns and revenue grew only 4.8% year over year, second-quarter 2021 revenue skyrocketed 39% to $1.9 billion. Of course, this strong performance wasn't solely due to an easy comparison. Much of it has to do with impressive execution from the company.

Consider that Chipotle's digital sales during Q2 increased about 49% year over year -- and that was on top of 216% growth in digital sales in the year-ago quarter. Further, the company opened 56 new restaurants while only closing five during Q2. It turns out that Chipotle's ongoing investments in data-driven marketing campaigns, drive-thrus, its digital loyalty program, new menu items, and operational efficiency are paying off nicely.

A group of people eating Chipotle at home

Image source: Chipotle Mexican Grill.

An attractive valuation

While Chipotle's price-to-earnings ratio of about 90 may seem expensive on the surface, strong revenue growth combined with operating leverage should lead to huge earnings-per-share growth over the next five years, easily justifying this premium valuation. Indeed, analysts' consensus forecast for Chipotle's earnings-per-share growth over the next five years is a whopping 58% annualized.

If investors are uneasy about analysts' optimistic outlook, consider management's commentary in Chipotle's second-quarter earnings report. "Strong restaurant level economics combined with significant restaurant growth should allow us to optimize earnings power for many years to come," said Chipotle CEO Brian Niccol in the company's second-quarter earnings release.

The company's operating leverage is certainly showing up nicely in its recent financials. Chipotle's restaurant-level operating margin hit a record high of 24.5% in Q2 2021.

Based on Chipotle's business momentum and its strong earnings potential, shares arguably look like an attractive long-term investment at their current valuation.