Jenny McCarthy -- Steak Date with Brian Urlacher

Another "maybe couple" alert -- this time it's former Playboy Playmate of the Year Jenny McCarthy ... and Chicago Bears superstar linebacker Brian Urlacher.

TMZ shot footage of the two leaving Mastro's in Beverly Hills together last night ... following a romantic dinner at one of the most expensive steak joints in town.

The two tried to sneak out the back door of the restaurant ... where an SUV was waiting -- but when you're as big as Urlacher ... it's hard to go unnoticed.

Seems Urlacher has a thing for famous blondes ... he BRIEFLY kinda/sorta dated Paris Hilton a few years ago.

Calls to both reps have not been returned.