Hot Wheels Cake

My oldest just turned FIVE. How are we here? He was just a tiny baby not too long ago. If you’ve been around here for any amount of time, you know my boys are obsessed with all things cars, trucks, and construction. This Hot Wheels cake is the perfect cake for little racers.

My boys have birthdays just a few weeks apart, and so this year the birthday themes were Monster Jam and Hot Wheels. I must say this has been my favorite year for cakes! In years past, we’ve done construction cakes (with matching party favors) and even a Paw Patrol cake. 

Things to Know About This Hot Wheels Themed Birthday Cake

• 100% homemade. This is a 3-layer 6-inch cake made with a variation of my chocolate cake as the base and decorated with vanilla buttercream.
• Thick chocolate layers. This cake recipe yields a thicker cake with a tighter crumb, yet it’s still incredibly moist and spongy. You’ll want the thicker cake layer to accommodate the tunnel in the cake. 
• Some skills are required. Bakery cakes can be expensive, and I had so much fun (and a bit of stress) making this Hot Wheels birthday cake from scratch. It takes time and a little bit of skill, but you can apply the frosting, fondant, and decorating techniques to future birthday cakes, too. You’ll notice some flaws in my cake, I am embracing them. You will learn from my mistakes!
• Make it your own. I set out to make a Hot Wheels cake with a tunnel for toy cars running through the bottom cake layer. Ambitious, but it paid off! If you don’t feel like making the tunnel, you can simply skip that step and assemble the layer cake as usual, but I have to say it was such a HUGE hit with his friends.
• Consider how to store and transport. My cake carrier was JUST tall enough to keep the cake stored airtight without the decorations. I transported it in the cak carrier and assembled onsite where we were having the party.

Prepare the Buttercream

First, prepare the buttercream frosting you’ll use to fill and frost your Hot Wheels birthday cake. Refer to the printable recipe card for the full recipe amounts and detailed instructions.

1. Make the frosting. Beat cold butter for 5-10 minutes until it’s whipped and super fluffy. It will grow in volumn and turn whitish in color, then gradually add powdered sugar, alternating with vanilla and heavy cream. Whip the frosting well in between each addition.
2. Color the buttercream. Give the frosting another good whip so it’s fluffy, then lower the mixing speed and slowly add a few drops of Electric Blue color, and one drop of Royal Blue to the frosting. Mix and add additional color as needed until the frosting is an even color. If needed, see my full tutorial on how to color buttercream for details.

How to Make a Hot Wheels Cake With a Tunnel

Before you assemble your layer cake, you’ll need to level the baked cakes using a cake leveler or a serrated knife to trim off the domes so the layers are even and flat for stacking. I go into the steps to assemble a layer cake in detail in my post, How to Make a Layer Cake. I recommend reading through it if you’re new to building layer cakes. 

• Secure the cake. Place a 6-inch cake board over the two halves, leaving the tunnel open in the middle. Cut two holes in the cake board, one on each side, then, place the dowels through the holes in the cake board and into the bottom cake layer.
• Add the top layers. Now, take out your assembled and chilled top cake layers. Carefully place them over the dowels. When you’ve stacked the cake, liberally crumb coat the outside with buttercream again, and smooth it out so the sides of the cake are as even and flat as possible. You may need extra buttercream around the bottom of the cake as it is slightly wider than the top. Return the cake to the fridge for 20-30 minutes so that the frosting can set properly.

• Frost the cake. Use a large piping bag to pipe the blue buttercream around the outside of the cake, starting and the bottom and working your up to the top. and spread a thin layer on top of the cake. Smooth out the piped frosting using an icing scraper, filling in any gaps and rescraping as you go. After your layer cake is evenly frosted, I recommend placing the middle track through the cake. It can stay there until it’s time to serve.

Fondant Decorations

I used fondant squares to create the black and white checkered flag pattern on the sides of the frosted cake and the orange loop track on top. Grab a package of pre-colored fondant at craft stores like  Michaels, Hobby Lobby, or Walmart.

Checkered Flag Pattern

You’ll need less than 4 ounces of fondant for the squares. You can cut your fondant squares up to 48 hours ahead of time. If you do, arrange them in a single layer in an airtight container to store for later. Cutting out the squares is easy:

1. Roll out the fondant. Use a fondant roller or rolling pin to roll out each color to an even ⅛” thickness.
2. Cut out the squares. Next, use a small square cookie cutter to cut out squares in each color. The cutter I used is ⅝”. Alternatively, you can use a ruler and pizza cutter to measure and cut  (I’ve also seen plunger cutters and multi-cutter squares, but I have not personally used them). You’ll need approximately 40 squares of each color, depending on how much decoration you want to do.

It’s best to apply the fondant squares to the cake when the buttercream is fresh. If you’ve already frosted the cake and are applying the squares later, use a toothpick to gently scratch the buttercream before you place the fondant on top. This helps it adhere to the cake. Or you can use piping gel.

I opted to make a few different arrangements of the checkered pattern, taking inspiration from various cakes I’ve seen online. I just love how it turned out and how it’s a bit randomized.

Fondant Number

In addition to the checkered pattern, I cut out a fondant number “5” using a cookie cutter. I laid out the black and white pattern, then very gently smoothed it over with a rolling pin so the squares would stick together. Afterward, I cut out the number, gently removed the cookie cutter, and left the “5” to lie flat overnight until it was dry. Since the fondant will wilt with time, I recommend placing the number on the finished cake right before serving.

Orange Fondant Loop

The fondant loop that I made as a cake topper took several days to dry, so give it plenty of time. The fondant should be thick enough so it (hopefully) won’t crack, but still thin enough so it dries completely. 

1. Roll out and cut the fondant. I recommend planning your loop using a piece of actual Hot Wheels track. This way, it’s roughly the same width and you can trim the excess off the sides. Roll out the orange fondant to ⅛” thick, and using the track as a guide, trim the edges with a pizza cutter or knife. Make the strip longer than you think you need at first, as you can always trim it back.
2. Shape the loop. To make the loop, use a wide cup or cylinder covered with a piece of parchment paper. Loop the fondant around the cylinder with the parchment paper in between, and place it on a sheet pan lined with parchment paper. Trim the ends as needed. Finally, place the fondant loop in a cool, dry place for several days to dry. 
3. Decorate. To place it on the cake, consider using a large spatula or cake lifter. I transported it in a separate container and placed it after my track was attached and assembled.

Hot Wheels Cupcakes 

Since I had no intentions of slicing this cake at the party, I served our attendees cupcakes. It’s so much easier than a slice of cake! Meanwhile, the kids enjoyed sending the car around the track and were amazed at the tunnel. They all wanted a cupcake with a chocolate tire! 

I made these Hot Wheels cupcakes from my favorite chocolate cupcakes and the same vanilla buttercream I used for the cake (I saw the idea on Pinterest from Chloe’s Cupcakes).

To decorate, I split the batch of buttercream into thirds and dyed it orange and blue, and left the third uncolored/white. I piped the frosting with a large French star tip following the same method as my rainbow cupcakes. Afterward, I topped each cupcake with a chocolate tire (see below). For the flames coming out of the chocolate tires, I used leftover orange buttercream and a size 21 tip.

Chocolate Tires

I topped my cake and cupcakes with edible tires. You can make these with black fondant or melted chocolate. Since I was serving them to the kids, I opted for chocolate tires. I used these tire molds from Amazon. I found the two medium-sized tires, although they’re different patterns, worked best. 

1. Prepare the chocolate. To make the chocolate tires, I used my candy melting pot, Ghirardelli melting wafers, and black oil-based gel color to dye the chocolate darker. You can buy black melting wafers, but I find that they don’t taste as good. However, if you’re using the tires only as a decoration, that’s a more cost-effective option or simply use fondant.
2. Fill the molds. You’ll need to pour one tire at a time, so a candy melting pot is helpful in keeping the chocolate at a consistent temperature. Otherwise, use a double boiler or a microwave, but make sure not to overheat the chocolate (see how to melt chocolate). Once the molds were filled, I refrigerated them until they were set and repeated it for as many as I needed.
3. Add a metallic shimmer. Afterward, I painted the center hub caps using edible silver shimmer. I think it gives them a nice touch! To make homemade edible shimmer, combine edible glitter with a couple of drops of vodka (don’t worry, it evaporates), clear vanilla, or lemon extract. Then, use a paint brush to brush the shimmer over the center of the tires. 

Make Ahead and Storage

• Make the cake layers in advance. Get a head start and bake the chocolate cake layers up to 2 days in advance. To store, wrap the cooled cakes in plastic wrap. Keep them at room temperature, or you can freeze the cake layers for up to 1 month. Thaw the cakes before you assemble and frost them.
• Store the leftover cake. You can keep the finished cake covered airtight at room temperature for a day or two, unless you live somewhere warm and humid, in which case, store it in the fridge. Remove any plastic decorations before storing the cake. The fondant will wilt and weep with time, so I recommend enjoying leftovers sooner rather than later.

More Birthday Cake Ideas

• Cookie Monster Cake 
• Dinosaur Cake
• Mickey and Minnie Mouse Cupcakes
• Elmo Cupcakes
• Confetti Cake