Prepare the cake mix according to packet instructions, but make cupcakes instead of one large cake. Spoon the batter into cupcake cases in a cupcake tin.

Bake and allow to cool completely.

To make the frosting, place the butter in an electric stand mixer and whisk until light and fluffy. Gradually add in the icing sugar, followed by the vanilla extract. If the frosting is too stiff, add heavy cream one tablespoon at a time until you reach the desired consistency.

Place the frosting into a piping bag and snip off the end. Pipe the frosting in circular swirls on top of the cooled cupcakes.

Warm the jam slightly, then whisk until smooth and runny. Use a teaspoon to drizzle over the top of the frosting, then finish with a gummy eyeball on each cupcake.