Out in Harahan, Jason Seither could play it safe and go with the tried and true when it came to po-boys at his Seither’s Seafood restaurant. But when he got involved with the annual Oak Street Po-Boy Festival back in 2009, something inside him lit up.

“I’ve always been a very creative soul, but when I first started Seither’s, it was more traditional,” said Seither, who opened the shop back in 2004. “But after doing the festival, I realized that people are looking for something different and off the wall, out of the box. So I was thinking maybe I should start doing some of my creations at the restaurant, so it took off.”

That’s why Seither’s has taken the crown for best specialty seafood po-boy three years running. First came the seafood au gratin po-boy in 2012, followed by the blackened shrimp and avocado version in 2013. When he heard there might be a similar entry in 2014, Seither went all sushi in 2013 and came up with the Rock ’n’ Roll, which took the blackened shrimp and avocado and added cucumber as well as Asian sauces — dragon, eel and fire — along with toasted sesame seeds.

These aren’t one-offs, by the way; since he’s been playing with these ideas for the past six or so years, Seither offers innovative specials on his menu throughout the year. Since last year’s competition, by his count, he’s trotted out about a hundred different po-boy creations as specials on his menu.

This year, he’s going with a grilled softshell crab po-boy — “Not too many people that do a grilled version,” he said — complete with carrots, cilantro and an Asian remoulade for more of a Vietnamese, bahn mi feel.

That inventiveness is in keeping with the spirit of a festival that’s become practically overstuffed in less than a decade of existence, starting with about 1,000 in attendance in 2007 and hitting about 50,000 last year.

To cope with the growth, organizers moved one of the music stages a few blocks off Oak Street to spread out the foot traffic and opened the gates an hour earlier at 10 a.m.

Seither’s is just one of 40 food vendors, including many of the popular Oak Street shops. The two main stages will feature music from eight different acts, including headliners Jon Cleary & the Absolute Monster Gentlemen at 4:30 p.m. on Oak and Eagle streets and the Rebirth Brass Band at 4 p.m. on Leonidas and Willow.

Local bars such as Maple Leaf Bar, Live Oak Café, Oak Wine Bar and Ale on Oak will be featured with live music on their “Saloon Stages.”

New features for this year include the return of an art market, featuring 25 local artists, and the expansion of activity further down Leonidas Street, according to festival organizer Adam Ross.

But most of all, expect lots of surprises piled on crusty French loaves.

“The po-boy fest,” Seither said, “has inspired me to be more creative.”