Make 2 sponge cakes (26x23cm) and freeze them overnight to make cutting easier when making this R2-D2 birthday cake. Remove from freezer and cut while frozen, on morning of party. Cut legs and body extension out of one cake.
Place on foiled tray and add rolling iceing (blue and white needed). Make red and silver colours by adding food colouring to the white. Takes 90 min to ice.