An onlooker told website HollywoodLife: 'Miley was with her publicist and told her to hang on for a second so she could come over to the Sprinkles cupcakes area and get a mini-strawberry and a mini-red velvet cupcake.
'Miley was like, 'You don't understand, Sprinkles is my thing,' and said her mom 'has a cupcake problem' too.'
While attending the star-studded event in Los Angeles, Miley was quizzed on rumours she has reunited with former boyfriend Liam Hemsworth.
However, she shrugged off the questions, saying only: 'Shhh! I'll never tell. My lips are sealed.'
The 18-year-old star is preparing to tour Liam's native Australia and she can't wait to get back on the road again.
She told US TV show 'Extra': "I love being on the road and travelling."
Miley and Liam, 21, split last August after around a year of dating, before reconciling the following month and eventually splitting again in November.