The words Give Hope, written on the smallest tier of the cake and reflected in a mirror beneath, top off the message of support.
A smaller cake with the same Daffodil Day decoration was gifted to the Hawke's Bay Cancer Society.
Ms Johnson was inspired to do something different with the window display to raise awareness for Daffodil Day, after she was asked by Cake Stuff owner Donna Kyle to design a cake for the fundraising event.
"It's just so unique and unusual," Ms Kyle said. "It draws everybody in and is a fantastic way to raise awareness."
Hawke's Bay Cancer Society centre manager Kay Collins was blown away by the positive display. "It's absolutely amazing, when you look into the mirror and you see 'Give Hope', that is just such an important message."
Cake Stuff will be selling daffodil shaped chocolates for $3.50 and cupcakes for $3, with all proceeds going to The Cancer Society. Collectors will also be out on the streets of Hawke's Bay gathering money for Daffodil Day tomorrow.
Hawke's Bay shop owners have been dressing their windows for the Daffodil Day Paint the Town Yellow competition.
Moys Bros Jewellers Ltd in Hastings took out first prize, winning a $750 Hawke's Bay Today-sponsored advertising package. In second place was Cake Stuff, which won a $300 advertising package.