If you’d like your sponge cakes to have a super-smooth, flawless finish then follow this simple step-by-step guide by Claire Fitzsimons to learn how to ice a cake like the professionals.

You will need:

• Round sponge cake
• Buttercream for filling and coating the cake
• Sugarpaste (please refer to a particular project for amounts)
• Round cake drum 7.5–10cm (3–4”) wider than the cake (if you don’t want the drum to show then use a cake card the same diameter as the cake)
• 1.5cm (½”) width ribbon
• Non-toxic glue stick

Covering the Cake

1. If the cake has a domed top, cut it flat with a serrated bread knife. Smear a little buttercream in the centre of the cake drum then place the cake upside down on top of it.
2. Cut the cake into layers and fill them with buttercream, jam or both. Coat the top and sides of the cake completely with a thin layer of buttercream. This is called a crumb coat and prevents stray crumbs from getting into the icing as well as helping the sugarpaste to stick to the cake.
3. Place the cake in the fridge to chill for 20–30 minutes. This will set the buttercream and make it easier to cover the cake.
4. Knead the sugarpaste well on a non-stick surface until it is smooth, pliable and completely crack-free. At this stage, only dust the board with a little icing sugar if the paste starts to stick to the surface.
5. Measure the top and sides of the cake so you know how large the sugarpaste will need to be when it’s rolled out. For example, if using a 15cm (6”) cake that is 7.5cm (3”) deep, you will need to roll out the icing a little larger than 30.5cm (12”) across.
6. Lightly dust the work surface with icing sugar. Take care not to use too much as this will dry out the sugarpaste, making it difficult to work with.
7. Roll out the paste, gently lifting and frequently rotating it as you roll. This will prevent the paste from sticking and help to keep it in a circular shape. Do not turn the paste over. The paste needs to be approximately 5mm (¼”) thick; place spacers on either side of the paste as you roll to help ensure an even thickness.
8. When the icing is rolled out to the correct size, flip it onto the rolling pin towards you. Place the edge of the sugarpaste closest to you against the front side of the cake and lay the paste over the cake, moving the rolling pin away from you as you unroll the paste. This action reduces the possibility of trapping air bubbles under the paste. SK Sugarpaste is less prone to stretching and cracking than softer sugarpastes, making larger cakes easier to cover.
9. Smooth the top with your hand then work around the sides to lift out any pleats. Don’t be tempted to squash pleats or creases into the cake. Work gradually around the sides of the cake, gently lifting out any creases with one hand and smoothing down with the other.
10. Smooth and polish the top surface and sides with a smoother. Using two smoothers, one in each hand, will give an even smoother surface and prevent any finger marks.
11. Remove any air bubbles by pricking a tiny hole in the centre of the bubble with a scribing tool or sterile glass-headed pin then rubbing over it with a smoother in a circular motion to ease out the air and seal the hole.
12. Trim the excess sugarpaste from the base of the cake with a sharp knife and smooth any rough edges with the straight edge of the smoother.

Covering the Cake Drum

1. Roll a sausage of sugarpaste the same length as the circumference of the drum. Dust the work surface with a little icing sugar and roll the sausage out into a 5mm (¼”) thick strip and approximately the width of the board. Trim one side of the strip with a sharp knife to create a straight edge. Dust the strip with a little icing sugar and gently roll it up like a bandage.
2. Brush a little cooled, boiled water onto the cake board before carefully unrolling the sugarpaste bandage around the cake. Gently push the cut side of the strip up to the base of the cake as you unroll it.
3. Overlap the join and cut through both layers. Remove the excess flaps of sugarpaste and smooth over the join with the smoother before smoothing the rest of the surface.
4. Trim the excess paste from the edge of the drum with a sharp knife then attach the ribbon to the edge of the drum with non-toxic glue.