This year my son is having his birthday party at the community pool. He, like his dad, are both spoiled brats & only want me to make them a cake. I almost only bake cakes for their birthdays. I enjoy baking & decorating and guests always talk about how delicious the cakes are, but if I get them in the habit of cakes they will want them all the time! He wants a minecraft "cake" cake. It is a very simple design with 3 colors (white, brown & a little red) and in the game looks smooth like fondant. I've worked with MMF before, making him 2 transformers cakes BUT we lived in Alaska & the party was indoors. Last year he had a BC frosted cake and even refrigerated up until serving and indoors we were pushing the limits of how long it would stay together. 

I would like to do as much as possible ahead of time (even completing it the weekend before because I also have food to prepare/cook day before/of) but don't know what will be the best route to take for the elements. It's already in the 80's during the day & getting pretty humid. His party is April 18th so I know it will be a little "worse" by then. There is a refrigerator at the pool that it can go into but I worry about it sweating.

Any help/advise/game plan is highly welcomed, for my sanity and the success of his cake!

In my country which is tropical weather, most use fondant especially for outdoor cakes. Personally, I don't like fondant so I minimised the usage. I'm not sure what design you plan on making but maybe you can use fondant (white), chocolate (brown), royal icing (red).

I tried using white chocolate and fresh cream before but it couldn't last. I've never tried BC, how did it go?

I'm in Hawaii, so also very tropical! It seems the kids like the marshmallow fondant (I'm guessing bc of the super high sugar content) & found a recipe today for a chocolate marshmallow fondant that people said tasted great. I think I will use regular MMF for the white (top of cake & halfway down the sides), gel dye MMF for the red (there's very few small red squares on top of the cake) & the chocolate for the bottom (halfway up the sides of a square cake). 

The BC tasted amazing but the party was in a warehouse. There were cargo doors open & huge overhead fans but by the time the kids got their pieces & we were packing up at the end of the party the BC was getting pretty soft. Of course it didn't stop us from eating it once we got home & refrigerated it! 

In a perfect world I would like to complete the baking, crumb coat, cover with fondant & freeze over the weekend prior & thaw a few days before the party. I've read a couple blogs that accomplished that task successfully, but all were in "normal" climates without heat & humidity! 

I've never tried making my own fondant so I'm not sure how it will turn out. All the fondant I've used are store bought. I'm a newbie with fondant, I find it too sweet and my clientèle prefers no so sweet cakes.

So I'm not really sure if fondant can be refrigerated because I tried it before and it turned soft when it thawed though it did harden again after some time. I'm from Singapore by the way. 

I live in the tropics too and so far never had an issue with buttercream ( I make both, American and Swiss meringue) or my homemade fondant. I used mmf fondant before, but it doesn't do well in my fridge, so I use my regular rolled fondant these days. The only thing I could never accomplish is chocolate decorations or ganache on the cake (inside is fine).

 Normally I refrigerate until delivery/ pick up. Never had an issue. Always making sure it's not in direct sunlight.

 If your BC started "melting" minutes after you removed it from the fridge there's something wrong with your recipe I would guess. Mine stays in shape for hours.

 Yes, the fondant starts "sweating", but only for a little while and then dries up.

 if you want vivid colors, I recommend you use fondant over your BC.

I think I'm going to go with MMF.

My BC softened up I'd say 45 mins to an hour after we took it out of the fridge. I somewhat question how cool the cooler was at the venue we were at. The cakes were placed in the same fridge as sodas and the sodas we had weren't as cold as coming from a home fridge. We were also right next to one of the cargo doors that was open, not in direct sunlight but close. The cake was fine before we left home, traveling to the location & when we got there and waiting for it to be taken back to the cooler. It was also fine once we took it home & refrigerated it again.

If I decide to bake, crumb coat & freeze ahead of time, how close to the party date should I take out to thaw & finish with MMF? Should I thaw in the fridge or counter top & keep them wrapped in plastic wrap until they are thawed? I have prebaked cupcakes & frosted with regular store bought frosting for one of my sons school parties. They turned out fine but the thawing time was pretty quick & it was just frosting slathered on. The cake I made using MMF before was made early the morning before the party, cooled all day & decorated the night before with finishing touches the morning of, but I don't have enough time to do it that way this time, unfortunately.