This fast-food chain you've probably never heard of is making a killing selling $8 burgers

"Burgers shouldn't cost $3," the website for Super Duper Burgers proudly declares.

The San Francisco Bay Area fast-food burger chain has garnered a cult following for its extra juicy, double-patty burgers that cost $8.50 with cheese. The company says it sources ingredients within miles of its restaurants.

The chain is now looking to grow its fan base by expanding from 10 locations to 13 by early 2018. Super Duper Burgers also said in a recent statement that it was in preliminary talks to launch international outposts, though we don't know where yet.

Here's what it's like to eat at Super Duper Burgers, a favorite Bay Area fast-food chain:

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