I have been asked to make another cake for the hospital I work at to feed about 100 people.
Thank goodness no tiered cakes this time, just a really large sheet cake. I am planning on making two 12 x 18 sheet cakes, single layer,  placing them side by side and icing the whole thing. 

1.  They want one vanilla ( All Occassion Downey Yellow butter cake, which I have made before in a 12 x 18 pan ) and one chocolate.  Which chocolate cake is used in the Rose factor chart?  I would really like to make the chocolate domingo cake but I don’t know if it will even work in a 12 x18 sheet pan.  The heights of each cake would need to be fairly even.  I know that I can get a full 2 inch height from the all occassion downey yellow butter cake from my previous cakes.

2. I am going to put a filling in the cakes but here is the problem.  When the cake is completely done I can’t fit it in my fridge.  ( It’s too big )  So I am going to need fillings which can stay at room temperature for a day.  I plan to fill and ice the cake the night before. ( they will be well wrapped in the fridge until then)  The icing will be the white chocolate mousseline buttercream, so I know that will be ok for 1 day at room temperature.

I am thinking maybe the light whipped ganache for the chocolate cake.  But I have no idea for the vanilla cake. 

3.  Do I need to syrup the cakes since they will be sitting out at room temperature for 1 day?

Any thoughts or advice would be really, really appreciated.

It would be easiest on you if you can have two separate cakes, and present them side by side on the table.  Even though I have a walk in cooler at work, when a customer is looking for that much cake for a corporate event, I always suggest this and they go with that idea.  Sometimes both cakes are decorated and put out, sometimes just one of them is decorated and ready for a ceremonial first cut by the guest of honor or company rep; and the second cake is being cut and plated by staff so people can be served quickly.

Liza - 25 May 2011 10:25 PM

I am planning on making two 12 x 18 sheet cakes, single layer,  placing them side by side and icing the whole thing. 

I’ll chime in along with Jeanne, will that fit in your car?  Or would you be able to frost and decorate at the display site?  It’s so long, you might need something like heavy duty cardboard or particle board to support it.  Maybe you’ve thought through all that already.

1.  Which chocolate cake is used in the Rose factor chart? 

  All-American Chocolate Butter Cake.

I would really like to make the chocolate domingo cake but I don’t know if it will even work in a 12 x18 sheet pan.

The leavening adjustment for the Domingo is complicated, bascially you have to scale the baking soda up with the rest of the batter in order to fully neutralize the sour cream (Rose says that cakes with sour cream that hasn’t been neutralized taste terrible).  Which means that all of the leavening adjustment has to come out of the baking powder portion of the total leavening.  I would be happy to help if you decide to go that route, but it would be an experiment that might need some tweaking to be perfect.

2. I am going to need fillings which can stay at room temperature for a day. 

I know the LWGanache says one day at room temp, but if it were me, I would make sure the cream has plenty of time left on its expiration date, boil it before chilling and whipping, and include a little alcohol (brandy, rum or even flavorless vodka) in place of a little of the cream in order to really make sure it would be well-preserved.  Maybe I’m being overcautious?  You could also consider the mocha light whipped ganache in RHC, it is absolutely wonderful.  I don’t know if you have or feel like getting hazelnut paste, but hazelnut mousseline is a divine combination with white chocolate and the domingo cake. 

But I have no idea for the vanilla cake. 

There’s always lemon curd or apricot lekvar (I think the CB calls it apricot puree, p. 335).  Either of those could be used alone as a filling or combined with mousseline buttercream. 

3.  Do I need to syrup the cakes since they will be sitting out at room temperature for 1 day?

  I would, just because they are large and might get a little dry around the edges from a longer baking time.

Great information, Julie. Liza, I have to agree with Jeanne about making the 2 cakes separately. G_d forbid you drop the whole thing trying to transport it and end up with nothing to serve and you have to face 100 people who were promised cake! Remember how that worked out for Marie-Antoinette?

I would syrup the cakes and use a mousseline buttercream (flavoured) for the filling. I have had no problem with my mousseline sitting at room temperature for a day or two.

Thanks everyone for your help, but they decided to go with a grocery store cake to save money.  Which is actually just fine with me.  Two 12 x 18 inch cakes, one with cookies and cream filling and one with lemon cloud cream filling would have been alot of work and time.  Not to mention making the hospital logo for both cakes out of royal icing and all the fondant lettering. 

Now I can concentrate on my birthday cake for Sunday. 

Oooo, what will you choose?

Dark passion chocolate cake with cookies and cream filling, frosted with dark chocolate ganache.  My first chocolate band turned out really well so I am going to try a marbled one for my cake.

Sounds wonderful! 

You may already have a filling recipe you like, but I must say that I would jump at the chance to use the choc chip whipped cream again, it tastes like an upscale cookies and cream filling.

Can’t wait to see it, especially your band!