Rolled fondant provides a blank canvas for the most intricate cake designs. Creating a textured diamond pattern on fondant to make it look like quilted fabric can be done using a tool called an embosser. Quilted fondant cakes are perfect for baby showers -- drape a large sheet of quilted pastel fondant loosely over a square or round cake to give the illusion of an actual quilt. Another popular cake design is the purse-shaped cake. Quilting in shiny black fondant gives a vintage feel to these chic sweets.
Roll out the fondant to 3 mm (1/8 inch) thickness on your pastry mat or large sheet of parchment paper, sprinkled with cornstarch to prevent sticking. Trim the edges to the desired size with a straightedge cutter or pastry wheel.
Run the pastry wheel or embosser lightly over the fondant in diagonal lines going in one direction. Use a ruler to space the lines evenly and guide the embosser.
Repeat the diagonal lines from the opposite corner to create a diamond pattern.
Lift the fondant carefully from your work surface and drape it on your cake. For best results, ice your cake with a thin layer of icing -- sometimes called a crumb coat -- before placing the fondant on the cake. The crumb coat of icing will help the fondant stay in place on the cake.
Press the fondant on the cake very gently and smooth any bumps or wrinkles. Trim any excess fondant with a sharp knife, straightedge cutter or pastry wheel.
The ridged embosser tool is recommended because it gives a stitching effect. If you don't have access to one, a pastry wheel or small pizza cutter will do the trick. It is easier to make a precise pattern on a flat sheet of fondant than to decorate an already covered cake.