boyfriend simpson jessica carl Jr fast food

But no, they're not dating - just friends, of course!

Jessica Simpson was spotted with the new dude (who co-stars opposite Gerard Butler in Law Abiding Citizen) leaving Jane's House late last night, and here are the deets!

An inside source tells X17online that Jess was there with BFF Ken Paves to celebrate the birthday for twins Evan and Taylor Hart. "Jessica and Evan weren't there together as a couple. In fact, I believe Evan has a girlfriend. Jess is just friends with all of them."

Oh and get this - Simpson even picked up the bar tab for everyone at the club. Hot damn! Talk about being generous.

Still, the two do look cute together. So much for romance!