I've been asked to make a black Forrest cake for 90 people for a wedding next month. (Chocolate cake filled with cherries and fresh cream). Issue is, it needs to travel on a 5 hour drive!

How do I safely get a wedding guest to transport a cake with fresh cream filling for this long? Freezer blocks were my first thought but I'm worried they won't be enough. (Australia middle of spring, could be up to 30 degrees). Car will be air con though. Would another type of cream filling work that isn't so fridge-dependent? I think buttercream would be too sweet.

Also, do I need to worry about the stability of that type of cake and it sliding?

Thanks :)

will this be a tier cake? or a flat rectangular cake?

oh i just saw your other post so it is a flat rectangular cake --

properly whipped whipped cream freezes nice and corrugated cardboard boxes surprisingly provide reliable climate control especially when you add the frozen freezer packs -- i tested a room temperature cupcake with all butter smbc in full noon memphis sun on a 100 + degree day and it was fine in there for a couple hours and the wind even blew it off the porch -- if the cake is already frozen or at least cold and you seal it in a corrugated cardboard box and add the freezer packs you should be fine  -- it will defrost as it sits out after it arrives --

my freezer packs are wrapped with a paper towel to collect condensation then sealed in a plastic bag --

if the whipped cream is under whipped you could run into problems with ice crystals forming and then when it defrosts it gets weepy so have a real good whip on the wc -- i do this all the time and no worries done properly

You can also add some gelatin to your whipped cream to give it some sort of stability.  Not too much of course, you don't want a cream jelly

however i do recommend your cake to be frozen when you box it -- or at least cold from the fridge -- your driver should take cake straight to venue but if they're gonna stop for lunch the cake needs to be out of the sun and they should get it to go kwim -- 

you need to school the driver about how to handle the cake -- 5 hours is doable -- 5 hours plus stopping and visiting aunt louise or going shopping for the wedding gift uh ugh

Yes, definitely chilled or frozen! I had a chilled bf cake one day in the cake that went jumping up and down as normal  (roads here are terrible) and ended up with half of the whipped cream squishing out on the sides. Thinking back about that still gives me a chill. Gelatin and freezer - especially on a 5 hours drive in summer :/

and you only guarantee the cake to the delivery car -- after that and being five hours away there is no repair service no guarantees beyond that

Five hours journey does not sound safe to me, even if it is frozen, unless it travels in an electric coolbox or freezer truck. Why would people order something so peculiar and order it from someone so far away? Bit of heat and the whipped cream starts sliding away from the layers - it's a disaster waiting to happen. 

Thanks for the tips everyone!

The bride is ok with it not being fresh cream in the middle, but would like a layer of some type of icing with the cherries, so there is a layer of "white" in between the chocolate cake layers.

suggestions on a more sturdy icing/filling? I've never made SMBC (not common in Aus) but plan to give it a go. Is it sturdier than standard buttercream (to me that's butter and icing sugar with flavouring). Buttercream might be too sweet with the cherries, but I'd run into the same transport issues with cream cheese icing. Hmm?!

Thanks.

i use smbc and i often have whipped cream and fresh strawberry filling -- the key to all this is climate controlling your cake during the delivery -- butter gets melty in the 90's f -- 32c -- so you simply have to secure the already coldcake -- corrugated cardboard is very nice to use for this -- you seal the cold cake in there -- add in some ice packs containing the condensation and it will hold an already cold cake for hours and hours 

Sounds like the way to go with the corrugated boxes. Now on a mission to find some!

... As a side nite, I made SMBC for the first time last night... I'm in love with it! So excited that it worked :-)

on good -- nice milestone with the smbc --

i get my boxes from a storage center -- you have those there I'm sure? ours sell the big boxes as do our uhaul places where you can rent trucks for diy moving day -- 16x16 inch box fits nicely into my car