Aaron Carter's back to the grind since coming out as bisexual ... taking his talents to a gay bar.
The singer's headlining Thursday night at Hamburger Mary's near his hometown in Brandon, Florida. The joint's known for its burgers and drag queen shows. While the performance comes just 4 days after announcing he's also attracted to guys, we're told Aaron actually booked the gig a month ago.
Aaron will perform for about an hour ... and the performance will include a compilation of his old hits and newer songs. The VIP ticket package -- which includes a meet-and-greet -- is sold out but limited tickets starting at 10 bucks are still up for grabs.
In case you're wondering ... tonight is NOT drag night.