Shares of GrubHub (NYSE: GRUB) surged in early Thursday trading and finished the week up 1.7% following a very bullish note from Oppenheimer concerning the online takeout meal ordering service.

As reported on StreetInsider, Oppenheimer sees recent price weakness at GrubHub as an opportunity for investors to buy into the stock at a good price. Indeed, if you give credence to the forecasts, the analyst observes that "our $50 target implies 60% upside" to GrubHub shares.

How is that possible?
Since hitting a recent high of about $47 in late April, GrubHub shares had shed 35% of their value prior to the Oppenheimer endorsement (they had already begun bouncing back from their lows). And according to the analyst, the company itself has lost little of its attractiveness.

"Concerns over margin pressure from investments in a delivery network, and competition from Uber" have weighed on the stock, according to Oppenheimer. "Weak Google Trends data" has reinforced these concerns, while corollary data from "a competitor" citing "weaker transaction data in Chicago and New York" has added to the worries.

Regardless, with GrubHub shares now selling for just 36.6 times free cash flow but pegged for an incredible 55% rate of annual earnings growth, the shares are arguably undervalued today.

Granted, many investors who look at GrubHub will be frightened away by the sky-high price-to-earnings ratio. The stock currently sits at approximately 90 times earnings, which looks very expensive. But between its strong record of free cash flow production (which is not fully reflected in the GAAP earnings number), its rip-roaring growth rate, and solid balance sheet (which shows no debt but plenty of cash) -- plus the most recent endorsement from Oppenheimer, this is one stock worth a look.

This $19 trillion industry could destroy the Internet
One bleeding-edge technology is about to put the World Wide Web to bed -- and if you act soon, it could make you rich. Experts are calling it the single largest business opportunity of our time. The Economist is calling it "transformative." But savvy investors could someday call it "how I made my millions." Don't be late to the party -- click here for one stock to own when the Web goes dark.

Rich Smith has no position in any stocks mentioned.

Want to learn how to invest?

Get a free 10 week email series that will teach you how to start investing.

Delivered twice a week, straight to your inbox.