Position a rack in the center of the oven and preheat the oven to 180° C

Grease and line 2 x 16cm cake tins with baking paper

Whisk together the flour, brown sugar, baking powder, bicarb, and salt

In the bowl of a stand mixer fitted with the whisk attachment, combine the tahini, buttermilk, water, oil, egg, vanilla and sesame oil

Whisk on medium speed until the mixture is smooth and caramel in colour

Gradually add the dry ingredients, using a spatula to scrape down the bottom and sides of the bowl as necessary and whisk until just combined

Pour the batter into the prepared tins and bake for 30 - 35 mins or until cooked through and a skewer inserted into the center of the cake should come out with just a few crumbs attached

Cool completely in the tins before removing

While the cake is baking, make the shards by lining a small baking sheet with baking paper and sprinkle the sesame seeds on it

Place the sugar and water in a small pot and bring to the boil

Swirl the mixture until it is combined (do not stir) and boil until it starts to reach a dark golden, amber colour

Carefully pour the caramel over the seeds, moving the pan so that all the seeds are covered with the caramel

Set aside to cool completely

FROSTING

Add all the ingredients for the frosting, except the sesame oil, in the bowl of a stand mixer fitted with the whisk attachment and whisk until the mixture is creamy, smooth, and a light brown colour.

Whisk for about 5 minutes, scraping down the bottom and sides of the bowl with a spatula a few times

Add the sesame oil, give it a good mix and decorate the cake with the frosting as you desire

Break the cooled caramel into shards and decorate the cake