The stock has increased more than 168% over the past two years yet still sells at a price-to-earnings ratio of about 10. After the dividend was slashed from $0.60 a share in 2009 to $0.20 a share in 2010, the distribution climbed to $0.85 in 2013.

The business is growing with cheap U.S.-produced feedstock and the existence of lucrative markets abroad for its finished products. In the process, the business has spun off two other companies that complement its operations. While Valero Energy (VLO 0.99%) looks good in many respects, let's compare this parent company to its two different spinoffs.

Refiner, exporter, and more
First and foremost, Valero is a crude oil refiner, the largest independent refiner in the U.S. In addition, the company operates a diversity of midstream assets to supply its refineries. Complementing these operations are 11 corn ethanol plants and export facilities to send gasoline, diesel, and other petroleum products to Mexico and Latin America. Valero also has more than 7,400 domestic "marketing sites," including Texaco, Shamrock, and the recently spun-off CST Brands (CST) stores (more on those below).

Valero enjoys the advantage of being in the U.S. and thus in close proximity to crude oil of various grades. One particular advantage is Valero's ability to refine heavy crude oil coming from Canada. This heavy oil sells at a significant discount to Brent crude, giving Valero a greater profit margin. The abundance of natural gas not only offers Valero a cheap energy source to run its operations but presents an opportunity to make methanol for domestic use or export. Expect a decision on whether Valero will pursue this methanol opportunity later this year.

This hydrocarbon cost advantage shows up on the bottom line. Earnings increased from $1.18 a share in the first quarter of 2013 to $1.54 a share in the first quarter of 2014. The quarterly dividend increased from $0.20 a share to $0.25 over the same time period. Cash and temporary cash investments more than doubled. Admittedly, 2013 wasn't the best year for Valero, but earnings and the stock seem to have rebounded in 2014. A $420 million share buyback for 2014 won't hurt, either.

The master limited partnership
On Dec. 11, Valero launched master limited partnership Valero Energy Partners (NYSE: VLP). In February, Valero Energy Partners paid a quarterly distribution of $0.037 a share. The next distribution in April increased to $0.213 a share. Don't expect percentage increases like this to continue each quarter, but the company does plan on 20% annual increases for the next three years.

One way Valero Energy Partners will deliver on that 20% goal is to expand the network of midstream assets operated by the partnership. Current assets feed three of Valero's refineries in Texas and Tennessee. That leaves 10 other U.S. refineries and their oil supplies as potential assets that could be added to the partnership. During its most recent earnings conference call, the company stated that additional unspecified assets would be added sometime in the second half of 2014.

So right now, Valero Energy Partners is a fee-based, logistics-oriented master limited partnership with the aim of having steadily growing revenue translate into steadily growing distributions. The company also anticipates a distribution coverage ratio of 1.1. With the likelihood of more Valero midstream assets joining its operations, that 20% distribution growth might just happen.

Retail in the U.S. and Canada
Operating more than 1,900 retail outlets in the U.S. and Canada, CST Brands was the first of the Valero-related companies, spun off on May 1, 2013. CST claims to be one of the largest independent operators of convenience merchandise and fuel in North America. Its U.S. operations are concentrated in the U.S. Southwest and California, while Canadian stores are in the southeast. Sixty-one percent of its stores are in Texas.

At the time of the spinoff, CST had $1 billion in debt, more than $300 million in cash, more than 68% ownership of its stores, and the momentum of more than $13 billion in revenue in 2012. Unfortunately, that momentum hasn't translated into earnings. Over the past year, quarterly earnings have steadily declined from $0.66 a share to $0.14 a share. Revenue has declined as well.

In fairness, the retail gasoline/convenience store market is highly competitive, and CST has been working to improve the customer experience at its stores. The company has been beefing up its convenience food menu and adding more stores to its network. CST plans on expanding its practice of razing and then rebuilding stores to add square footage to promising store locations.

Final Foolish thoughts
The easy investment advice here is to avoid CST Brands until its earnings start to recover. One could argue this is a turnaround story; I prefer to see concrete evidence of earnings growth over hoping for better times. I'm most excited about the master limited partnership. Revenue and distributions look to grow, particularly after additional assets are transferred from the parent company. This should drive the stock higher, a winning combination of capital gains and income.