“Extra” spotted “Grey’s Anatomy” star Kate Walsh in a lip lock with a mystery man over the weekend!

Now, we’re revealing who the sexy stud locking lips with the gorgeous starlet is… and take our word for it -- this mystery man will make you say McSteamy and McDreamy who?

We snapped up footage of Kate and her new real-life love, boyfriend Alex, getting spicy at the Mustard Seed Café in Los Angeles.

Kate recently told Us Weekly, “We’ve been together for awhile, and he’s just a Dreamboat.”

Make that a McDreamboat, Kate!