Warren Buffett, arguably the greatest investor of all time, has amassed a fortune exceeding $100 billion. The business he runs, Berkshire Hathaway, is one of the world's largest corporations today. This kind of success naturally has people wondering how he did it. 

Spoiler alert: There is no secret formula. Instead, what the Oracle of Omaha suggests doing is actually quite simple. 

Warren Buffett.

Image source: The Motley Fool.

Invest early and often 

Buffett bought his first stock when he was just 11 years old. Aside from being an investing genius, he credits time as the critical ingredient of his success. "I started building this little snowball at the top of a very long hill. The trick to having a very long hill is either starting very young or living to be very old," he said at Berkshire's 1999 annual meeting. 

In other words, let compound interest do the work for you. Most investors focus intensely on trying to achieve high returns when simply putting money to work early and often is the key. If you were to invest $10,000 in a low-cost S&P 500 index fund in 1991, you'd have over $200,000 today with literally zero effort. And adding small sums of money, either monthly or annually, would significantly boost the amount you'd end up with. 

It's all about time in the market instead of timing the market, letting your money do the work for you. While Buffett strongly advocates against picking individual stocks, for those willing to put the time and effort in, security selection might be the right course of action. And here's one stock investors can take a look at that fits Buffett's criteria. 

A stock Buffett would like 

Chipotle Mexican Grill (CMG 0.19%) is a popular restaurant stock that I think Warren Buffett would love. The fast-casual pioneer has competitive advantages, a strong consumer brand, and exhibits pricing power, all characteristics that the legendary investor seeks.

Chipotle's sheer scale, with its 2,853 restaurants primarily in the U.S., gives it a leg up on smaller chains when it comes to vendor relationships and marketing initiatives. And being widely recognized has resulted in the business focusing closely on the customer experience. For example, Chipotle's digital app, currently 23 million members strong, made it possible for hungry customers during the pandemic to order ahead for pickup or delivery. This bolstered consumer trust in the brand. 

Additionally, as food and labor costs have increased over the years, Chipotle has been able to pass these expenses on to customers. For example, in response to wage increases in June, management raised menu prices by 4% with no significant impact on its business. Pricing power is something Buffett would certainly cheer about. 

The takeaway 

While we can't all achieve a 12-digit fortune someday, what we can do is study and learn from one of the investing greats. Warren Buffett's strategy of investing early and often in order to let the power of compound interest take over is so simple that anyone can follow it. The challenge, however, is actually having the patience and discipline to go through with it. 

The key to building wealth over the long term is extremely simple -- but it's not easy.