Starbucks has given investors plenty of cause for celebration over the years, and initiatives to increase food sales and expand its international footprint give the coffee giant avenues to continue delivering stellar capital appreciation, but there are other companies that might have even more promising outlooks. 

With the goal of identifying stocks that have tremendous growth ahead, we assembled a team of three Motley Fool investors and asked each to pick a company that has high-flying potential. Read on to learn why they think Restaurant Brands International (NYSE:QSR)Shake Shack (NYSE:SHAK), and Shopify (NYSE:SHOP) are companies that could be primed to soar.

A man drawing growth lines.

Image source: Getty Images.

Think fast (food)

Dan Caplinger (Restaurant Brands International): Starbucks has seen tough times lately, making almost no headway over the past two years as leadership changes and competitive pressures mount. Fast-food companies have tried to pick up the slack, and Restaurant Brands International has made several moves that have helped its stock nearly double since the beginning of 2016.

The name of the game for Restaurant Brands International has been expansion. RBI made a big acquisition in 2014 when it bought Canada's prized Tim Hortons. The food giant now believes Tim Hortons should be as ubiquitous in the U.S. as it is north of the border, and its coffee and pastry options have already made it a much more direct competitor to Starbucks than Burger King ever was or will be. The more recent announcement that RBI would purchase Popeyes Louisiana Kitchen further shows how much urgency the fast-food giant feels about fleshing out its product lineup.

Burger King's fundamental strength has also been solid. Promotions like its choose-your-favorite meal options have helped drive traffic, and memorable new food items have also gained the burger chain some attention.

In a tough environment for restaurants, Restaurant Brands International has done a better job than many in keeping its stock price moving higher. If it can keep up its momentum, it could keep soaring more than Starbucks in the months and years to come.

Shaking up the burger market

Rich Duprey (Shake Shack): There's a lot to recommend against investing in Shake Shack and only a few in favor of it, but for those investors with a sufficiently long time horizon, the better burger joint will likely reward the patience.

Call it a fad, or better yet, a trend, but high-priced hamburgers are a thing right now. There's an explosion of eateries willing to charge you a lot for your ground-beef patty. From Shake Shack and The Habit to Five Guys and Smashburger, the lowly hamburger has been elevated to something of an art form, but the profusion of burger stands is reaching a saturation point, and sales are starting to slow. With seemingly as many burger restaurants on every street corner as there are Starbucks, quarterly comparable sales are turning negative.

It's even happening at Shake Shack, which last year continued to enjoy the buzz surrounding its IPO in 2015. Last quarter, though, comps fell 2.5%, and management expects them to be flat for the year. It also saw a 4% decline in average weekly sales at domestic company-operated locations, to $86,000.

While it's true I've never been much of a fan of Shake Shack's stock, and I find its current valuation frothy, its growth plans are much more reasonable than the competition, and its targeted store openings, along with international expansion where it licenses the brand, is a much more enduring strategy than what the competition has, so the Shack will likely outlast it. Moreover, because it customizes its menu for each city in which it opens, it has the capability to target local flavors, explaining why it can still get lines forming around the block when a new restaurant opens.

It is starting from a small base of only a few dozen restaurants, meaning there is a heckuva lot runway still in front of it, and although weekly sales fell, they remain so much higher than the rest of the industry. Shake Shack remains a growth stock that will undoubtedly face some headwinds, but there is a case to be made that with enough time, it could see returns comparable to the coffeehouse.

Simplifying online retail

Keith Noonan (Shopify): Online retail company Shopify has already seen its share price explode roughly 180% over the last two years, but the stock still has huge growth potential, and it looks like the best is yet to come for shareholders.

Shopify's platform delivers a simplified online vending solution that comes with a wide range of functionality and customization options -- a hugely valuable service for small and mid-size businesses that otherwise lack the resources needed to design and maintain an online shopping portal. Last quarter saw its subscription services revenue increase 60% on the strength of new client additions, while the commission revenues that Shopify generates from each sale grew 92% thanks to an 81% year-over-year increase in merchandise volume.

At the heart of Shopify's explosive potential is an ability to grow by adding new customers while also benefiting from the sales growth achieved by companies that are on board with its platform. The costs and hassles associated with switching to a different sales portal suggest that the company already has a sticky source of recurring revenue generation, and, with the online retail market still relatively young and growing at a rapid clip, there's huge room for subscriber and sales volume expansion.

Even though the company trades at roughly 12.5 times forward sales and has yet to record a profitable quarter, there still looks to be a big opportunity in Shopify stock. The company's approach to growth seems to be similar to that of Amazon (a one-time competitor that has since partnered with Shopify), with an emphasis on innovation and setting up long-term advantages over short-term results, and an impressive business model combined with favorable market trends suggest that its stock could continue to soar. 

Keith Noonan has no position in any stocks mentioned. The Motley Fool owns shares of and recommends Shopify. The Motley Fool is short Shake Shack. The Motley Fool has a disclosure policy.