The 19-year-old actress sported a loose-fitted grey top with no bra and tight jeans and boots.
She was photographed holding up a cup, which she took to Instagram to explain, writing, “I felt the need to point out that I am carrying a milk filled oil can cup I got from Cars Land... f**k with me.”
The Modern Family star has long been an advocate of positive body image.
Earlier this month, Winter took to Twitter to defend her right to wear whatever she wants, writing, “Pretty annoyed about the focus on the fact that I wear shorts, and the commentary that I'm 'squeezing' into them or the idea that it's not OK for me to wear shorts. It's SUMMER. Get over it. It's hot, I'm obviously going to wear minimal clothes. I'm not going to suffer in a turtleneck to please anyone."
For more from the body image advocate, watch the clip below!