Resurgent pandemic outbreaks apparently didn't end McDonald's (MCD -0.75%) growth momentum. The fast-food giant said last week that comparable-store sales expanded for a second straight quarter. The third-quarter earnings report came with other good news for investors, including rising margins and ample cash flow.

Let's take a closer look at why those metrics make the restaurant stock more appetizing today.

Four friends sharing a meal at a fast-food restaurant.

Image source: Getty Images.

Traffic is back

The major growth headline is that McDonald's global business continued to rebound despite a return of COVID-19 restrictions in several key markets. Comparable store sales rose 13% compared to a 2% decline a year earlier when many of its locations were temporarily closed, or at least closed to in-store dining. Revenue also improved compared to 2019, with sales up 10% on a two-year basis.

The results are, "a testament to our unparalleled scale and agility," CEO Chris Kempczinski said in a press release. "We continue to execute our strategic growth plan and run great restaurants."

The best news was that customer traffic is rising across all of its biggest fast-food markets. That metric had been falling before this quarter, with declining guest counts being offset by higher average order size. Now, McDonald's is getting a lift both from higher spending and increasing traffic.

Handling price increases

McDonald's spent the past year cutting costs and making its restaurants more profitable. Those initiatives were valuable at a time when the economy is seeing accelerating inflation.

Operating margin rose to over 46% of sales compared to 37% a year ago. The management team had been hoping to keep that metric in the mid-40% range but COVID-19 sent it much lower last year.

That profitability rebound helped Mickey D's earn roughly $8 billion in operating income over the last nine months, compared to $5.1 billion a year earlier. Earnings per share this quarter rose to $2.86 from $2.35.

Is the stock a buy?

Heading into the report, most investors were looking for McDonald's to notch a solid growth rebound in 2021, with sales rising about 20% compared to the pandemic-influenced 2020. Earnings were forecast to jump 50%, too, thanks to a full profit margin recovery.

Those predictions look a bit too conservative considering the chain's latest results. Fast-food fans are visiting its restaurants more often and ordering more food to go and for home delivery. And McDonald's isn't seeing a big earnings pinch from food inflation, in part because people are spending more heavily on premium food and drink products.

Add in the dividend giant's growing payout, and McDonald's stock looks like a solid bet for investors seeking a balance between growth and income -- without taking on too much risk. The industry leader's shares haven't kept up with the market surge in the past year, but that's only more reason to like the stock today.

McDonald's business took just a small step backward during 2020 and has now fully recovered. The prospects for sales growth are strong as shoppers tilt spending toward mobile ordering, delivery, and drive-thru. And the chain still enjoys some of the best profitability and cash flow in the business. Those assets should support solid returns for investors who simply hold on to the stock.