R2D2 cake

Ingredients

• 85g unsalted butter, softened
• 251g sugar
• 1.5 large eggs
• 2 tablespoons blue colouring
• 1 1/2 tablespoons cocoa
• 3/4 teaspoon vanilla extract
• 219g flour, sifted
• 3/4 cup buttermilk
• 3/4 teaspoon salt
• 3/4 teaspoon cider vinegar
• 3/4 teaspoon bicarbonate of soda
• 4 oranges' rind
• 450g mascarpone
• 227g ricotta
• 1.13 kg icing sugar, sifted
• 4 tablespoons sour cream
• 2 teaspoons vanilla essence
• 1 cup blueberry jam
• 1/2 cup hot water
• 42g butter, melted
• 284g marshmallows
• 6 cups rice krispies