Sunday, April 15, 2012

How to Make a Firetruck Cake

I would like to preface this post with this note:
I am not a cake artist. I do not make "carved cakes." I rarely make 3D cakes of any kind. When my good friend asked me to make a fire truck cake for her son, I obliged, knowing it wasn't exactly my "wheelhouse," but her son is my guys' best friend, so how could I say no?! (Only later did she tell me that she didn't mean a 3D cake. Alas!)

The cake is far from perfect, but I'm sharing it, and maybe if I make another one, I'll follow my own suggestions below... and it will be more perfect. 

What You Need:
2- 9x13" cakes (baked and cooled) - I used doctored cake mix for this cake.
1-2 batches Decorator's Buttercream Icing
Approx. 8 oz. of homemade or store-bought fondant
Icing Colors in red, black and yellow
Silver Pearl Dust
Sturdy base for cake - I would recommend foam-core board or particleboard

Getting Started:
Start by baking the cakes. I used cake mix and just doctored them up to make them taste a little yummier.
*Note: Level both cakes. Even if you think they're level. Level them with a cake leveler anyway. Just to be sure! (I didn't, and that's one of the reasons the cab of my truck is leaning forward.)

Cut and assemble your base. I don't have a photo of this because this was another of my failures with this cake. My base was just cardboard, so it was not strong enough to support the weight of the cake. That's why the front of the cake is leaning forwards a little... that, and I didn't level the white cake.
I recommend using foam-core board. Cut it to about 12"x 4-1/8" Then, cut another piece of foam core smaller, about 10 1/2" x 3". That way, your cake "stands" above the black base the cake will "drive on." (If you want, cover that in black contact paper so that it blends in with the black board below, and you won't see the base at all.)

This base will then go on to whatever board or plate that you want to serve the cake from. I used cardboard covered with black paper and contact paper- to resemble a road.

Mix up a batch of Decorator's Buttercream Icing. You'll want to take out about 2 cups for white, and 1 cup for grey. The remaining 3 cups will be colored red.
See my post about Coloring Icing, and the one about No-Taste Red Coloring for more info on getting the colors right.

Making the Fondant Accents:

The fondant accents were totally freaking me out... but in the end, they were about the easiest part. But if you make them 24-48 hours before you assemble the cake, it will make it even easier. 
You will need about 8 oz. of either homemade or store-bought fondant. I used marshmallow fondant. You need most of it to be white, but about a golf-ball sized amount of black, and just a pinch of red and yellow.
You can use the top and bottom of an Icing Tip #12 to cut the circles. The large circles come from the base of the tip, the small circles from the top.

If you want them to actually dry hard, then you need to do one of two things. Either combine the fondant with some Gum-Tex or combine the fondant with an equal amount of Gum Paste. (You can buy either at the craft store, cake supply store or online.) I used Gum Tex, and only used 1/4 tsp. with about a baseball-sized piece of fondant, and that turned out not to be enough. My fondant never got hard enough to do with it what I wanted. So, use more Gum Tex. Maybe 1/2 tsp. or more.

I employed the five-year-olds to help paint the fondant silver. Use Silver Pearl Dust with just a tiny bit of clear vanilla. To add the sparkle to the pieces like the windows and the shield, I dry-dusted the pieces with the pearl dust (or let the five-year-olds do it).

Shaping The Cake:
Here's a Template for how to cut the cake: (if you have two different flavors.)
I think it will make more sense when you see it put together... although I have to say that I couldn't follow this completely since I decided I didn't need to level one of my cakes, and therefore they were different heights and not at all level!
*Note: I just realized that if you have just one flavor, you could save a lot of trouble... you would need just 1 1/2 cakes. And you would use two halves stacked on top for the bottom two layers... add one more half (or two)... and just cut into one of them where your "dip" is behind the engine. Hmmm. Next time.

Anyway! Start by cutting each in half lengthwise.
For the engine, you'll then cut one of the two halves into thirds, like you see above.
Cut the other cake as you see in the other template. Cut in half, then cut off the top third (about 4 1/8" in). Then take about 1 1/2-2 inches off one of the remaining chocolate halves. (Stick with me, it makes sense when you see it! Sorry I didn't take more photos!)

 Here's how you then assemble it... Bear with me because the photo and my description won't match 100%. (Due to my failure to level the darn cake!)

So... if I'd have done it right, the bottom of the cake is the whole length of the half cake. See?
Then you use two of the three "thirds" of the same cake to make the engine. (You could use all three, but I found that the cake was too tall and out of proportion with all three full pieces. You can see that I added a teeny, thin slice of the third to mine-- that's again because of my leveling issue.)

For the back, I would recommend just using the two pieces. You've removed the top 1/3 of the cake, so it should fit on the bottom layer flush... and for the top one, cut about 1 1/2-2 inches off to make the little dip where the dials and levers go. (Again, you can use the remaining 1/3 as another layer if you wish... it's pretty much the exact same size as the other pieces, so that's up to you. I used all three because it ended up getting rather short once I leveled it.)

*Note: I used Bake-Even Strips to help keep the cakes level... which in the end means that they are taller because I don't have to level off as much of the "dome" that forms. I highly, highly recommend these. If you have the "regular-sized" ones, you can just put them end-to-end around a 9x13 pan, and they work perfectly!

Glue the pieces together using icing. I would stick with a thin layer of icing, rather than trying to add another filling, just because this cake is a little wobbly, given its narrow, tall shape, so if you add any other reason for it to slide or squish around.... eek.
*Note: Add some icing between the front section and the back section. Again, if you just use one flavor, this won't be as much of an issue, but my engine started to crack forward a little at the end. I needed to add some icing between the sections to help glue them together as well.

Icing the Cake:

So, when you're icing this cake... if you don't have a lot of experience with icing cake that has been cut, you may want to make extra icing. The thing about cut-cake is that it makes LOTS of crumbs. It may be a good idea to do a "crumb coat" where you just get the whole thing iced, ignoring the crumbs. Allow that to set, then add the real coat of icing over it, thereby keeping most of the crumbs out of the icing.

Whether you crumb coat it or not, I would always start with the lightest color... and move on to the darkest color. Honestly, skipping the white would also be a good idea, and just make the whole thing red. I only added the white because that is what our fire trucks in our city look like. (Although in truth the top of the back is also white, but I had to draw the line.)

When you add colors like this, have a lot of paper towels nearby (or an extra bowl) to wipe off your spatula often. Getting perfectly straight, even lines, is darn-near impossible. This is where we embrace good enough.

If you use my Decorator's Buttercream Icing, or another "crusting" icing, you can smooth the icing with a Viva brand paper towel (other brands are embossed and will leave a pattern on the cake).

Voila! Ready for embellishments.

Finish the Cake

Everything on the cake is fondant... except the writing. To make the gauges and the shield on the doors, I used the Food Writer markers.
The cake was well-crusted, so I brushed the back of the decorations with clear vanilla to get them to stick.

Happy Birthday, Will, the "Rescue Worker!"

Click the Links Below to See:
How to Doctor a Cake Mix
Decorator's Buttercream Icing Recipe
How to Ice the Corners of a Cake
Fondant 101

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  1. Hi there - I love this cake and am planning on making it for my son's birthday in September. When looking at the stacked unfrosted cake pieces, I was wondering if I could just bake one cake in a rectangular loaf pan and cut out the "in between" section between cab and back? Do you think that would work? It probably would be a smaller fire engine but for a novice, maybe easier? Just thinking out loud :)) Thanks for your wonderful blog.

    1. Absolutely! After I made it, I thought the same thing... how much easier it would have been with one flavor!
      Good luck! Please let me know (see) how it goes!!
      - Beki

  2. Hi Beki. Thank you for the tutorial. I was wondering if I could get the dimensions of the finished cake...mostly the height.

    1. I'd say, depending on the height of each cake, you're looking at 6" to 8".
      Good luck.

  3. Hi-
    Great job! Your tutorial is by far the most helpful of all I have researched. I'm making a firetruck for this weekend and will utilize many of your tips and techniques (my client wants a fondant cake, though, which is better for me as I am hopeless at buttercream).
    One question: about how many servings did your cake provide? I need 35-40 (3 boxes of mix, maybe?)
    Thanks again for sharing...your little friends must have been thrilled!

    1. Marilyn,
      I would say this will feed 30-40 depending how you cut it.
      Perhaps you can do some cupcakes like in the link below for the side?

  4. Thanks for your help with this project. It turned out well with your ideas and tips.

  5. Hi Beki, can i make the whole cake (including decorate) 2 days ahead of the actual party, and put it in the fridge? Will all the fondant and buttercream be ok?

    1. Absolutely!
      My general rule for cake is five to seven days from making to eating.
      Keeping it in the fridge is a good idea, just be careful when you bring it out, if you're in a warm, humid climate, the fondant can get a little sticky and weepy.
      Good luck!
      - Beki

  6. Hi! This is the best post ever, my sons party is on Sunday and I am making a fire truck cake for him. I was going to use a thermomix cake recipe, but it is for a 24cm cake tin and I am making the size cakes that you suggest (9 by 13 inches)-so Im not sure how to convert the recipe? Do you know? or I will just use packet mixes like you said-was it just one packet mix per tin? or did you have to use two packet mixes per tin as its so large? Also, can I make the cakes on friday and do a white crumb coat. Then on Saturday do the red coat and decorations, etc?

    1. My best guess, as it's been a while, and I don't remember exactly, would be that I used about 7 cups of batter to make each cake. Each cake mix here, and most of my scratch recipes will make about 5 cups of batter. (A Google search found that 5 cups is 1.18 Liters... so each cake would take about 1.66 Liters of batter.)

      And yes, I think making and crumb coating Friday to decorate Saturday would be a great way to do it!

      Good luck!!

  7. I have been researching ways to make a fire truck cake and your instructions have been by far the most detailed and easiest to understand! I will be making this cake for a 4th of July birthday boy and am a little less stressed thanks to you! I will post the results when I complete it! Wish me luck ;)

  8. I am a beginner. What is the best way to cut it without it tumbling?

  9. Using this as my template to make my husband’s graduation cake from the fire academy. I’m not the greatest froster so I’m going to try and cover in fondant…which I’ve never done lol it’ll all be fine


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