An engineering firm has released a tongue-in-cheek forensic report into the reasons behind Prime Minister Jacinda Ardern's birthday cake failure - and it had nothing to do with the baking.
On Sunday, Ms Ardern took to Instagram to reveal a piano-shaped cake for daughter Neve's second birthday - propped up by a jar of lentils.
"Cake making lesson number two - don’t focus on making the cake look in proportion with little to no attention on structural integrity... there is a jar of lentils propping this thing up. Happy Birthday Neve! Thanks for ignoring all of the imperfections in life and just being a joy #PianoCake #australianwomensweeklybirthdaycakebook," she wrote.
After examining photos of the cake under construction posted to Ms Ardern's partner Clarke Gayford's Instagram page, Tonkin + Taylor structural engineer Alex Vink identified an issue with the baked treat's stability due to its shape.
He said the cake can be seen in three parts, including a base, middle section and a curved top piece.
"Based on the fact that the Prime Minister used a jar of lentils to prop the cake up, it would suggest that there was a stability issue. This issue is related to the shape of the cake and not the quality of the baking," Mr Vink said.
He said the cake's stability failure occurred due to its centre of gravity being "too far away from its pivot point."
Mr Vink noted that the upper part of the cake was "quite tall" and had been located "far away from the centre of the base of the cake."
"When the top piece was placed on the base, the base may have sagged slightly under the weight of the large top piece. This sag could have resulted in the top piece tipping over and falling off the cake base due to its high centre of mass."
He suggested a number of ways to make the cake design work without the lentils to prop it up.
Wrapping the cake in fondant may also have been used at the cost of the cake's taste and texture.
"For Neve's third birthday, the jar of lentils could stay in the pantry if the PM picked a more two-dimensional cake, like her fantastic bunny cake from Neve’s first birthday, but this wouldn't look as cool," Mr Vicks said.
He finished his report by adding that there are "a number of brilliant engineering-related designs" from the Australian Women's Weekly Children's Birthday Cake Book which the Prime Minister may consider for next year, including a gingerbread house and a train.
Tonkin + Taylor have offered free structural engineering advice for Neve's third birthday.