Begin by greasing and lining an 8x8” square baking tin with baking paper, ensuring the edges hang over for easy removal later.

Place the digestive biscuits in a ziplock bag and use a rolling pin to crush them into fine crumbs, leaving some larger chunks for added texture.

In a saucepan, combine butter and golden syrup over low-to-medium heat. Stir continually until fully melted and well blended, approximately 3-5 minutes.

In a separate bowl, melt the dark and milk chocolate together in the microwave, using 30-second bursts and stirring in between until fully melted, about 1-2 minutes.

Pour the melted chocolate into the butter and golden syrup mixture, stirring gently until fully incorporated. Then fold in the crushed biscuits until evenly distributed.

Transfer the chocolate-biscuit mixture into the prepared tin, using a spoon to compact it evenly into the corners. Let the base cool at room temperature for about 30 minutes.

Once the base has cooled, take the Mint Aero Bubbles and gently press them into the top of the mixture.

Melt the milk chocolate and white chocolate in separate bowls, using the microwave method for convenience.

Using a spoon, drizzle alternating stripes of the melted milk and white chocolate over the top of your traybake.

Refrigerate the decorated traybake for at least 2 hours to allow it to set completely. Once firm, remove it from the tin and slice it into squares.