There's much debate over how Yum! Brands(NYSE:YUM) fast-food company Taco Bell will fare in the breakfast market. No matter what happens, Taco Bell has been rolling out some great marketing, calling out the likes of McDonald's (NYSE:MCD) by name. The move should prove to be a great marketing ploy to also get foodies interested in Taco Bell. But the growth story for Yum! could go beyond the breakfast menu.

First, what are Taco Bell's chances at breakfast success?
There's no doubt the breakfast market is huge, so it only makes sense that Taco Bell would try and capture some of it. The $50 billion U.S. breakfast market is something that every restaurant company should take notice of. The market is nearly four times Yum!'s total annual revenue. If Taco Bell can just capture 5% of the breakfast market, that would be a $2.5 billion increase in revenue -- which is 20% of Yum!'s annual revenue.

McDonald's is still a very tough competitor
Gaining market share in a fickle industry usually isn't that hard, since customers have little-to-no loyalty to fast-food chains. They will generally be drawn to whatever is cheapest. That's in part why McDonald's continues to own the breakfast market.

McDonald's offers a comprehensive menu of $1 breakfast items. And it plans to double down on the number of breakfast items priced at $1 for the near term. At year-end 2013, McDonald's had nearly 20% market share in the breakfast category among quick-service restaurants.

Burger King Worldwide (NYSE:BKW.DL) is the smallest of the three companies (by market cap). But it has managed to garner solid footing in the breakfast market, in part thanks to its popular croissan'wich. However, there has been a move to healthier items among consumers. McDonald's is already offering oatmeal, but Taco Bell plans to debut yogurt parfaits and oatmeal soon.

The real growth story at Yum!
While seeing Taco Bell make a push into the breakfast market is a positive for investors, as the move is relatively low risk, there are a number of other growth opportunities. China remains Yum! Brands' workhorse when it comes to generating revenue. The country generates double the revenue for the company that the U.S. does.

McDonald's still has a relatively small store base in China compared to the U.S. It's looking to change that by expanding into China more rapidly. However, Yum! Brands' KFC will have an advantage given its vast presence there -- meaning KFC has already had its pick of prime locations. And as McDonald's tries gaining a footing in China, it'll be competing with Starbucks for ideal locations.

Burger King entered the Chinese market nearly a decade ago, but it's yet to gain any meaningful traction. That's because McDonald's and Yum! continue to eat its lunch (so to speak) abroad. Burger King has less than 200 stores in China. Meanwhile, McDonald's opened 275 stores in China last year and plans to open another 300 this year.

Yum! stumbled in China during 2012 and 2013 due to quality concerns related to chicken at its KFC restaurants. But it looks ready to take McDonald's and Burger King head on in 2014. Yum! was able to raise KFC prices by 3% in China earlier this year, as the chicken issues look to be fading away.

A renewed focus on the U.S.
Yum! is also looking to gain better footing in the U.S. quick-service restaurant market. Part of that involves the rollout of Taco Bell breakfast items. Taco Bell does account for 60% of its U.S. operating profits. And Taco Bell has posted eight consecutive quarters of positive comps grow as of the fourth quarter of 2013.

As part of its plan to grow its U.S. business, Yum! is looking to increase its Pizza Hut and Taco Bell stores while also focusing on a smaller-format store that requires a lower initial investment. The company has set a long-term target of 8,000 Taco Bell stores; compare that to the less than 6,000 it had at year-end 2013.

Yum! has also launched a new store in Texas that will challenge Chick-fil-A. This is a big positive considering that Chick-fil-A passed KFC in annual revenue last year. And it did so with a fraction of the stores. There are only around 1,800 Chick-fil-A stores in the U.S. (heavily concentrated in the South) compared to KFC's near 4,500. This new store in Texas offers a limited menu and is focused on hand-breaded chicken sandwiches.

Bottom line
Yum! Brands is one of the best investments in the fast-food space. It has a large geographical presence and a number of key growth opportunities. It also offers a modest dividend yield at 2%. Trading at 18 times next year's earnings estimates, Yum! appears rather expensive. But its P/E-to-growth ratio of 1.7 is in-line with McDonald's and Burger King. And Yum! generates a return on equity that towers over its major peers at 46%. So, for investors looking for exposure to the fast-fast industry, Yum! Brands is worth a closer look.