Gloria MacKenzie of Zephyrhills, Florida won the $590 million Powerball jackpot last month. (Zephyrhills is 30 miles northeast of Tampa.)

It took her two weeks to come forward . . . and after last weekend, it seems like Gloria is still being mysterious about her money.

Someone matching Gloria's description had dinner at Buddy Freddy's restaurant in Plant City, Florida on Sunday . . . which is about 15 miles away from Zephyrhills.

She had two people with her . . . and she returned to the restaurant a little later to PAY the bill for EVERYONE in the place. There were about 180 people having dinner at the time, and the tab came to $2,600.

She threw in $50 tips for each of the servers and left, without saying who she was . . . but everyone in the place seems pretty sure that it was Gloria.