Proving that all you need is a great earnings boost, Green Mountain Coffee Roasters (GMCR) is up 12% — and climbing — after yesterday’s better-than-expected full-year and Q4 earnings report excited GMCR stock investors.

Green Mountain Coffee Roasters listed a profit of 83 cents per share of GMCR stock for its fourth quarter, nearly 10 cents more than analysts had forecast for the period.

GMCR revenue came in at some $1 billion, also beating Street forecasts quarterly revenue of $964.5 million. In all, GMCR saw a 16% annual revenue growth in fiscal year 2013 from a year ago.

As a result, GMCR is one of the morning’s biggest winners. And that tacks onto an already good year. Even though it’s shown some weakness in recent months, Green Mountain stock gained nearly 50% year-to-date before the stock jump today.

The question now is whether GMCR stock can keep the momentum going, though. Its success this year is in part because the company leaned on strong sales of its K-Cups — as revenues from the popular portion packs climbed 18% year over year.

Moving forward, however, Green Mountain may see increasing competition, as more store chains enter the market and grocery stores themselves get in on the action. This could cut into sales and slow GMCR stock.

Investors may recall that GMCR stock was one of the hottest momentum plays in 2011 … until the stock took a fall after a mid-year peak. It didn’t begin to regain upward momentum until mid-2012.