There comes a time when every fast-growing eatery ultimately hits that brick wall.

It would be insensitive for me to claim that P.F. Chang's (NASDAQ:PFCB) has hit the Great Wall, but it's clear that the casual dining operator behind the P.F. Chang's China Bistro and Pei Wei Asian Diner concepts is no longer that smoking speedster in the eatery circuit.

This morning, P.F. Chang's posted a dip in third-quarter profits as sales inched 14% higher to hit $231 million. Earnings fell to $0.25 a share after producing a profit of $0.31 a share a year earlier. Yes, that includes stock-based compensation charges and the need to account for certain pre-opening expenses as incurred instead of written over the term of the lease, but this is still a moribund operator at the moment.

Even that 14% top-line uptick is disappointing, because P.F. Chang's now has 239 units open -- 24% more than it had this time last year. In other words, average weekly sales are also dipping at the unit level.

Hoping to catch lightning in a bottle for the third time, the company opened a third concept earlier this month in its home turf of Scottsdale, Arizona. Taneko Japanese Tavern isn't in the same teppanyaki mold as Benihana's (NASDAQ:BNHN) or your local sushi specialist. It's more of a conventional casual-upscale concept with an exhibition kitchen and an emphasis on grilled and roasted Japanese dishes.

It's an interesting approach and not necessarily a bad one. Kona Grill (NASDAQ:KONA) has seen its stock more than double since bottoming out back in December with its eclectic concept that has an Asian influence. However, even if Taneko is a hit, it will be years before it grows large enough to have a material impact on P.F. Chang's financials. For now, the company's most pressing need is to succeed in winning back patrons to its flagship concept. That remains the Great Wall of worry here, and investors should steer clear of buying into the company until it can get its comps growing again.

Curious on what we've said about these concepts in the past? Check out:

Check out our suite of investing newsletters with a 30-day free trial.

Longtime Fool contributor Rick Munarriz has always enjoyed his meals at P.F. Chang's, but he does not own shares in any of the stocks mentioned in this story. He is also part of the Rule Breakers newsletter research team, seeking out tomorrow's ultimate growth stocks a day early. The Fool has a disclosure policy.