I'm making a 3 tiered stacked cake for my moms 80th birthday. I think I understand how to do the dowels in each layer for support, but my question is when I put the middle tier on top of the bottom tier, do I just use the card boards cut the same exact size as the cake or do I use the plastic support the same size or what? Also, when I get ready to "unstack" the cakes so that we can cut them, how do I keep the frosting from sticking to the card board or plastic support on the layer beneath? Hope that makes sense!!! This is my first three tiered cake and I will be making it next week. Wanna make sure I have all of the supplies needed before I start!!!!

When I do a tiered cake I use card board the size of the cake for middle and and top layers with dowel rods under. I also sprikle a bit of 10x sugar between the layers to help them from sticking. Hope this helps. Need anymore help send me a message, glad to help.

You can use either:
http://www.wilton.com/cakes/tiered-cakes/stacked-tiered-cake-construction.cfm

I use a circle of waxed paper to prevent sticking.

Those plastic plates that you can buy are to be used when you are using columns ( push pillars or the ones that connect to another upside down cake plate) they are not for stacked cakes. If you look in the gallery you won't see any of those scalloped edges peeking out between the layers.

mommachris

Again, you can use either...
Quote from Wilton:
"Step 2
Position the middle tier on the base tier, centering exactly.

**TIP: Finely shredded coconut or confectioner's sugar, placed in area where cake circles or plastic plates will rest, helps prevent frosting on the cake from sticking."

Smooth-edge plates are available, or use a size smaller if you don't want the scalloped edge to show.

Thanks everyone!! So when you put the powdered sugar between the layers to keep them from sticking, does it not change the taste of it all together, like make it too sweet? Also, if I was to use wax paper, do I need to put anything under the wax paper or just put it directly on the buttercream? Just don't wanna destroy the cake when I detach the layers.

You won't have so much p. sugar that it's overly sweet. Will you be keeping the cake chilled? That will help prevent sticking. If the cake gets warm and the frosting is too soft, I've seen the whole top layer of frosting pull off the cake when disassembled.

I use foam board (from Hobby Lobby or Michaels) as my separator plates. I cut the bottom one at least 2" larger than the bottom cake...hot glue 3 of these together and cover them either with clear contact paper (prevents grease spots) or decorative wrapping paper first, then the contact paper...place my bottom cake on, decorate and then proceed to the other cakes. BTW, I use 3 because its the perfect size for 7/8" ribbon to hot glue around the outside after you're finished decorating. The other cakes, meanwhile are each on 1 foam board cut exactly to the size of the cakes. I then sit those on a scrap of foam board (so I have something to hold onto while frosting (usually stick them together with a piece of tape). Then when its time to stack, just remove the tape off the bottom and grab your cake (with the exact sized separator underneath) and carefully drop onto the other cake. Works best for me when they've been well chilled. You can use a really sturdy spatula too! Some other people have recommended putting the dowels in but not pushing them all the way down, then when you put your cake on top, you don't mess it up and it will push the dowels down the rest of the way. I personally don't use this method too often because my cakes are too chilled for this. Also, I bought some bubble tea straws (you can get them at any Asian market) and use them as my supports inside. You just push them all the way down and cut exactly to size. Sometimes I push all the way in, then mark it, pull it out a little and cut to perfection. Once all three cakes are on and perfectly centered....make sure to walk around the cake to make sure they're even on all sides, I drive a dowel rod down the middle of all three. I take a wooden dowel, stand it next to the cake to measure the length...then subtract an inch. Finally, I sharpen it to a very sharp point (sometimes just use a utility blade for this) and start by pushing it down through the middle of the top cake. Once I hit the first foam board, I start hammering it down. You'll be surprised how easily it goes through. Then you can fix the top cake with a little buttercream. This method gives me the security of the cakes not moving, especially because I didn't make any pre-drilled holes in the foam boards...hence, no movement. Never had a problem with shifting. Once you're ready to cut, I do the top cake first (without removing the dowel). After the cake is gone and the dowel is revealed, I remove the dowel by pulling it straight up and out. Works like a charm.