John Mayer, Jennifer Aniston Rekindling Romance?

Is it back on for Jennifer Aniston and John Mayer?

The exes were spotted out on a dinner date last weekend, People reports.

Dining over a meal of oysters (aphrodisiac alert No. 1!), ravioli with mushrooms and black truffles (aphrodisiac alert No. 2!) and fish at New York City's Il Mulino on Saturday, Mayer and Aniston "looked like they were having a fantastic time," an eyewitness told the magazine.

That wasn't their only get-together either. The two ate out, albeit with four buddies this time, at Boston's Mantra restaurant the night before.

"They were friendly but regular," a restaurant staffer shared. "We wouldn't have noticed them if someone hadn't called ahead ...They just came in with their group and sat in the hookah bar and drank and ate."

After a whirlwind four-month romance, Mayer, 30, and Aniston, 39, split in August, a move initiated by the singer because he didn't "want to waste somebody's time if something's not right."

Are Maniston more than Friends again?