The 38-year-old South African actress made a Pinkbery employee's day Tuesday by leaving a $96.25 tip after failing to pay for her $3.75 tab.
Theron was enjoying a frozen dessert at a Hollywood Pinkberry location when she told the woman at the counter, Keila, that she'd have to return to pay the bill because she didn't have her purse.
Keila told TMZ that one hour went by before the Oscar-winning actress came to pay her bill, but she made up for it by leaving a really big tip.
"She got a mini with some toppings, which is $3.75," the Pinkberry worker said. "She said she'd be right back, and then she said she'd also be back within the hour and then she kind of took off."
Theron eventually returned to the store, with Sean Penn, and gave Keila a $100 bill to cover her $3.75 tab.
Asked what she'd plan to do with the bill -- keep it, sell it or spend it -- Keila said that she wan't sure the money was, "mine mine."
You can check out a clip of the incident, including Theron returning to pay her tab, below.