A crowd of about 30 curious spectators gathered at 5.30pm in the gallery as she crawled naked into the toffee tomb.
Asked what it was like inside, she replied: "Sticky".
At 8pm, she broke through one of the panes and was greeted by cheers from onlookers.
She emerged, covered with toffee, and blew kisses to the crowd.
"It wasn't as painful as I thought it would be. It was actually quite meditative," said Baldwin of Christchurch.
"Towards the end I remember thinking: 'I am going to get out of this'. It felt so victorious when I broke through."
The project referenced the modern "sugar-rush society", she said.