Emmy Rossum Ate 7 Cakes for Her Birthday
09/30/2014 AT 06:30 AM EDT
"I ate too much," Rossum told PEOPLE at the Rape Foundation's Annual Brunch in Beverly Hills on Saturday. "There were seven cakes. Seven cakes over the weekend. But that's what birthdays are supposed to be!"
Looking fantastic in a Lyn Devon dress and Louboutin shoes at the brunch (which raised funds for the Stuart House, a rape treatment center in Los Angeles), you'd never guess that Rossum had recently downed so much dessert.
"But then I went to Soul Cycle, so that's fine," she said, laughing.
Rossum also celebrated her birthday with the other sweet in her life, her boyfriend, writer and director Sam Esmail.
"We went to the opera and saw Traviata. And then we had a dinner party at my house. It was nine girls and my boyfriend," Rossum added. "Poor thing, or lucky him."
Either way, Rossum says her birthdays are going to change going forward.
"I hate aging," she said. "I'm going to start celebrating the anniversary of my 21st birthday from now on!"