Method

• 1.
  For the buttermilk jelly, soak gelatine in cold water for 5 minutes to soften. Whisk milk, vanilla and caster sugar in a saucepan until combined, Place over medium heat and cook, stirring occasionally, until hot. Squeeze excess liquid from gelatine and stir through milk mixture. Stand until cooled to room temperature, then stir through buttermilk. Transfer to a 22cm, 5L trifle dish and chill for 3 hours or until set (jelly can be chilled for up to 3 days).
• 2.
  Meanwhile, for butterscotch, combine all ingredients in a saucepan over high heat. Cook, stirring constantly, until butter is melted. Bring to a simmer and cook, stirring occasionally, for 8 minutes or until reduced slightly. Stand to cool completely (butterscotch can be stored, chilled in an airtight container, for up to 2 days).
• 3.
  To make the chocolate shards, thinly spread melted chocolate over a large piece of baking paper. Cover with a second piece of baking paper and roll up to form a 2cm-diameter cylinder. Freeze for 30 minutes, then unroll – the chocolate will break into shards (chocolate can be prepared up to 1 week ahead; roll up and chill instead of freezing).
• 4.
  To assemble, scatter brownies over jelly. Fold half the butterscotch through the whipped thickened cream, then spoon over brownie. Chill until needed.
• 5.
  Scatter caster sugar over banana and caramelise with blowtorch. Stand to cool completely. Top cream with caramelised banana, chocolate shards and remaining butterscotch to serve.