I was hoping to get a little advice/reassurance on a cake I have at the end of the month. It is a small cake, 3 tier. It will be covered in fondant and have fondant ribbon at the bottom of each tier (purple), white swirls and purple swiss dots. I will be using SMBC under my fondant.
The sticky part is the venue. It is an hour drive (our weather today was 80! Yikes!) to a beautiful park...that has waterfalls. The reception will be outside at the top of a waterfall. I'm not too worried about overspray, but it tends to be quite humid. Additionally the cake has to stand for 5 hours before cutting. I believe it will be under a tent at least to protect it from the sun.
I'd like to deliver the cake well chilled so it holds up better. I'm not certain however when the best time to do the piping/ribbon is. I'm a bit worried the purple will bleed onto the white when the cake comes up to room temperature, and also that the royal icing would break down in the fridge, when coming up to room (or outside) temperature or in the humidity. Also concerning the ribbon, I'm planning on brushing it with luster dust to give it an extra pop but both the fondant and luster dust will be purple.
I rarely do outside weddings and this one has me all sorts of nervous, especially when it's hot out and the cake has to stand for so long! I'd love any advice people have!
I would highly recOmmend using shortening based buttercream under the fondant. Use a very thin crumb coat so nothing is tempted to slide. A room temperature cake will hold up best since the condensation of a cold cake in a hot and humid environment tends to cause problems. I never use a merengue buttercream if the cake is to sit outside in a warm environment. That's just my opinion. Good luck!!