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Topic: Sheet Cake 12x18
joaneydoc75 09/24/2008 3:39 PM
I need help making a sheet cake 12x18. Would you recommend doing two layers? Would it be too large? How many cups of batter per layer? Or if I use boxes mix, how many boxes does I need? How many cups of icing to ice and decorate?

Please help.

Jeanne G 09/25/2008 10:03 AM
Is your pan 2" deep or 3" deep? Select the appropriate chart from here: It will tell you how many cups of batter, how many cups of icing, and number of servings.

Sheet cakes may be served as a single layer. They may be split horizontally and filled (calling torting) for two layers, or two cakes may be baked and stacked with a filling between them. (Stacking is not generally done with cakes 3" high.) Which approach you take depends on the look you are aiming for and the number of servings you need.
cami5271 09/25/2008 10:03 AM
I always use 4 boxes for a single layer 12x18....that's more then enough batter. Some folks use only three, but when I tried, it didn't rise all the way up in the corners, making my cake shorter than I like when I leveled it! 09/25/2008 10:09 AM


This link will take you to a Wilton Chart that lists info for all pan shapes and sizes.

If you layer sheet pan size its important to dowel well, use 2 cake boards between layers and if possible use a recipe with a firmer texture.

Good Luck!

sharridee 09/25/2008 3:55 PM
Jeanne G 09/25/2008 4:07 PM
Actually, Jerri, you never put a cake board between LAYERS ... but you do need to put a cake board and use supporting dowels between TIERS. If you are going to serve a slice of cake that has two layers, you need to be able to cut through both layers and not have a piece of cardboard in the middle! However, when you stack two separate cakes one on the other, each to be cut and served separately, then they are considered tiers and you do need each on its own board. (The difference between layers and tiers often causes some confusion.)

Whether layering or stacking, it is very important, as you point out, that the cake board can support the weight of the cake(s) on it without bending.
joaneydoc75 09/26/2008 8:56 AM
Thank you everyone for the responses I really appreciate it.

joaneydoc75 09/26/2008 8:56 AM
Do you need to use a heating core?
twinsmake5 09/26/2008 4:01 PM
I wish I'd never wasted my money on them. Lower your temp to 325 and bake away. I've also tried someone's idea of using a flower nail - but that caused a mess and holes in the cake. I've baked the 12x18 at the lower temp many times and it comes out great. I usually bake all my cakes at 325 anyway - just to be on the safe side. It'd be a good idea to line your pan with parchment paper. It's a big cake and you want it to come out safely! I also froze mine as I brainstormed over how you flip such a cake without it breaking. You can do this with two cooling racks - but I found it easier to maneuver a cold/firm cake into the right position if it's to be stacked. becky
wonderchic 09/28/2008 8:18 PM
I own two 12x18x2 pans & I LOVE them! I've made several cakes in them - each one 2-layer. I've had zero fails with them. I'll share what I do...

First, I have a 1/2" to 3/4" (?) thick piece of plywood for the cake board. I believe I got it cut approximately 14x20 (or just shy of that). I wanted to make sure it would fit into Wilton's BIG cake box! I cover it in wrapping paper then food-safe cellophane (the kind that you cover gift baskets with).
Second, I always use DUNCAN HINES cake mixes & I've gone onto their website & use their chart for mixing their cake mixes for this size of cakes (measurements slightly differ perhaps for better baking process). For 2 layers, I've always used 5 cake mixes total. Even after leveling I have PLENTY of scrap left over! I use TWO inverted flower nails spaced evenly apart & spray everything with the cooking spray that comes with flour already in it. I cook at 325 or SLIGHTLY under & I just keep my eye on it so I don't know how long I bake them for.
I let them sit for the 10 minutes before removing them from the pans after baking. Then I cover the cake with parchment, lay my largest cutting board on top & invert the pan & cutting board together at the same time. The cake comes out with NO problems. I do the same process to then invert the cake onto the cooling rack.
I level the layers after they cool. I set one layer onto the prepared plywood & apply the filling. Then I set the 2nd layer atop. I use simple grease-resistant cake cardboards well-dusted with powdered sugar to help move & stack the layers (I SLIDE them). I have never had any layer break. My first attempt yielded a slight crack across the middle before I got my method down.
As far as how much icing, it's hard to say. Check the wilton guide on that & make more. It's ALWAYS better to have too much than not enough!!
I typically use this size cake for 50 people. Around this area, you can hardly have too much cake!

Overall, to answer your question about this being too big as a 2-layer, I would feel weird making this cake as a single layer. Of course, perhaps again, that could be the area I live in...

I wish I had a better picture to share, but I'm not on my home computer so I had to use whatever I had on my phone. It's of the latest 12x18 2-layer I did. Yes, it DOES make a HEAVY cake to transport! LOL! This was a cake I did for my grandma's church's ladies' banquet. *Ok, I have to admit here that the eagle on the cake was done in all buttercream. I did each "feather" with a leaf tip. It was challenging but FUN! I actually got applauded by the church ladies for the cake! (wow)

I hope my LONG & detailed reply answers at least most of your questions!

Best wishes & have fun with it!
Ayanami 09/28/2008 8:23 PM
BES are a MUST!!! I do not recommend baking this cake without them. I use 4 whole boxes when I make chocolate, but I have found that vanilla or classic white cake mixes seem to bake less firm? Dense? than chocolate. The white cake mixes (pils or DH or BC) all seem to rise still gooey then spill over the edge. I would recommend baking a test cake first to determine how much batter you will need for your specific recipe of batter. I have made a "full" sheet cake (18x24) before that was layered. (4 cakes total) What a beast! My husband had to build me a wooden carrier to transport it & we covered a sheet of clean plywood with my fanci foil to use as the cake board.
karen 09/29/2008 9:28 AM
I just made one Friday. I finally treated myself to the professional straight sided 12 x 18 pan.
The directions with the pan called for 14 cups of batter for a 2" high cake. I used Duncan Hines mix. I put 2 flower nails in the pan and used bake even strips. It raised right up to the top.
I torted it and filled it with chocolate mousse and fresh strawberries and wound up with a 3" high cake.
I was pleased with the outcome. Does anyone know how many servings this would feed
in "real life". The person I made this for was having approx. 50 people. I hope it was big enough.
Any comments???
SweetLeigh 10/05/2008 4:07 PM
I just made two 12x18 cakes today. This time I used 2 yellow cake mixes, but I added two extra eggs and one lage box of vanilla pudding. Then I mixed up a box of orange cake mix and swirled that into the yellow. The first one I baked at 350 degrees and it was a little overdone around the edges. But the second one I baked at 325 and it came out perfect. Both rose to the top of the pan and they were very level.
Usually I'm making the large cakes to serve at church functions, so I want them to be easy to serve. And I want it to go far. So I normally make them just one layer. Although I thought about torting them, but I'm usually too lazy to mess with it!