What's the best companion to your Subway footlong sandwich? How about a free footlong cookie?

Starting in December, Subway is introducing a footlong chocolate chip cookie to a select group of restaurants across the country. The footlong cookie will become a permanent part of Subway's menu starting in 2024.

And just in time for National Cookie Day on Dec. 4, Subway will be offering a free footlong cookie with the purchase of a footlong sub sandwich at special stores in Chicago, Dallas, Miami and New York.

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National Cookie Day: Where to get a free footlong cookie at Subway

On Dec. 4, select Subway restaurants are being transformed into "Cookieway," and will be offering a free footlong cookie with the purchase of any footlong sub sandwich. The participating restaurants will be offering the free cookie from 1-6 p.m. local time, while supplies last. Here's where to find the footlong cookies:

• Chicago: 604 S Wabash Ave., Suite D, Chicago, IL 60605

• Dallas: 1222 Commerce Street, Suite 150, Dallas, TX 75202

• Miami: 2795 Collins Ave., Miami Beach, FL 33140

• New York City: 545 8 Ave., New York, NY 10018

“The overwhelming response we received from fans around the country last year let us know that we needed to make the footlong cookie a permanent addition to our menu,” said Paul Fabre, Senior Vice President, Culinary and Innovation at Subway, said in a press release.

Similar to Subway's popular regular-sized cookie, Fabre said the footlong version will be “thick, gooey, packed with chocolate chips and served warm – right out of the oven."

"It’s the perfect pairing with your favorite footlong sub and may even become your favorite footlong after the first bite.”

This article originally appeared on USA TODAY: Subway footlong cookie: Where to get it free for National Cookie Day