To make a truly impressive cake for a special celebration, bakers often stack cakes of different diameters on top of one another. Each stacked cake is called a "tier." Usually, the largest cake makes up the bottom tier and smaller cakes are stacked toward the top. You may stack two to five or more tiers. Each tier is normally a two-layer cake with icing or a special filling between the layers. The tiers may be stacked directly on top of one another, or they may be suspended above each other using columns (pillars) and separator plates.
Place each two-layer cake on a cardboard cake round. (The cardboard cake round for the largest cake should be at least two inches larger in diameter than the cake. The smaller cakes that will be stacked above should each be on cardboard cake rounds the same diameter as the cake it supports.) Each cake should have icing between the layers as well as on the sides and top of the cake.
Measure the height of the largest cake and cut four 6 mm (1/4 inch) diameter dowel rods about 1.5 mm (1/16 inch) shorter than that measurement. Dowel rods are simply rounded wooden sticks that you can buy in various diameters at any hardware or craft shop. Push the dowels down into the centre section of the cake, with each dowel far enough apart to support the weight of the next smaller cake. Gently set the second cake on top of the largest cake, centring it over the dowel rods. Note that without the dowels in place, the weight of the second cake would cause it to sink into the lower, larger cake.
Continue by measuring the height of the second cake, cutting four dowel rods 1.5 mm (1/16 inch) shorter than that measurement, and pressing them down into the centre section of the second cake so that the dowels will support the weight of the third cake. Repeat this procedure until all the cakes are stacked with dowel supports between each successive tier.
If you would rather have columns or pillars supporting each tier, you will still need four dowel rods in the centre section of each cake. Rather than stack the second cake directly on top of the first cake, on a hard surface such as a table, turn one of the cake separators over so that the four "legs" are pointing upwards. Press a column onto each of the legs, then add another cake separator with "legs" pointing downwards and pressed into the tops of the columns. Centre this two-plate-with-columns assembly on top of the dowel rods in the largest cake. Carefully centre the second cake on top of the plate-and-columns assembly.
Measure, cut and press four dowel rods into the second cake, make another two-plate-with-columns assembly and centre it on top of the second cake. Continue in this manner until all cakes are tiered. Note that all the separator plates must be of the same diameter.
If you have push-in pillars (columns), place the largest cake on a cake round that is at least two inches wider in diameter than the cake. Take the separator plate that the second cake will rest on and, holding the separator plate with "legs" down, centre it on the largest cake and gently press the "legs" into the icing to make light marks, then remove the separator plate. Push pillars into the largest cake, using the marks as guides. Place the "legs" of the separator plate downward and place each "leg" into the hole in the top of each column or pillar that you have already pressed into the larger cake. Place the second cake upon the separator plate. Mark the second cake with the "legs" of the next separator plate, align the push-in pillars with the marks, and press them into the cake until they stop; place the "legs" of the separator plate into the tops of the second layer of columns and put the third cake on the separator plate. Do not "mark" the top cake.
Have decorations already prepared and add them to the tiered cake on the table where it will be displayed and served. Always bring extra icing and decorations to the serving/building site to add ruffles or shell borders or to repair any problems that may occur during transportation of the cakes.
Never transport a tiered cake. Instead, assemble the tiers when you have the cakes at the table where the tiered cake will be displayed and served.