Although we don't believe in timing the market or panicking over market movements, we do like to keep an eye on big changes -- just in case they're material to our investing thesis.

What: Shares of Ignite Restaurant Group Inc (NASDAQ: IRG) are trading 9% higher in the afternoon after surging to a maximum intraday gain of nearly 14% on Thursday morning. The sit-down chain operator, which maintains more than 300 restaurants of three different concepts (Joe's Crab Shack, Romano's Macaroni Grill, and Brick House Tavern), trounced Wall Street's expectations in its fiscal first quarter last night.

So what: Ignite's quarterly revenue nearly doubled (up 82%) year over year to $214.9 million, ahead of even the optimistic analyst estimates for $210.2 million on the top line. The company also reported a narrow profit of $0.01 per share, well ahead of the $0.11 loss per share Wall Street had expected. The gains were led by an impressive 10% same-store sales improvement at Ignite's Brick House locations, which helped to offset a disappointing 6% same-store sales drop at its Joe's Crab Shacks, and a 4% same-store sales drop at its Romano's locations.

Ignite executives maintained guidance at roughly the same level as they had projected earlier, with full-year revenue reaching about $880 million on aggregate same-store sales that will range from flat to higher by 1.5%. That's roughly in line with Wall Street's projection of $878.6 million in revenue for 2014.

Now what: Ignite's shares have been rather volatile since the company went public in 2012, but the company's growth plan appears to be working. However, that also means that earnings have tanked, and its free cash flow has fallen from positive levels due to growth-phase spending. Investing in chain restaurants is always tricky, and weakness at two of the company's three brands is a cause for concern, as well, even though lousy weather is at least partly to blame. If you're still curious about this fast-growing company, do yourself a favor and stop by your nearest Joe's or Romano's to see if these are concepts worth investing in for the long haul.