Mini Bundt Cake Decorating Ideas

These creepy (and easy!) Halloween cakes are perfect for any party! Spongy mini buttermilk bundts are drenched with red glaze and speared with candy knives.

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Prepared killer Halloween cakes with red frosting and candy knives.

About Killer Halloween Cakes
Can you substitute the buttermilk?
Can you freeze buttermilk cakes?
Can you freeze the red glaze?
Can you make these cakes in advance?
How long do these Halloween cakes last?
notes & tips for these Halloween bundt cakes
More fun Halloween recipes
How to make killer Halloween cakes
Recipe Details

About Killer Halloween Cakes

Halloween is the perfect time to get in touch with your inner spookiness, and whipping up a batch of these creepy killer bundt cakes is the most fun way to do just that.

And while these DIY Halloween cakes might appear complicated to make, the only thing "difficult" part about them is applying the icing – and I, She Who is Perpetually Challenged in Realm of Cake Decorating, was able to decorate these a whole batch of mini bundts perfectly in one shot.

I know I always say this, but it's true for this scary Halloween cake recipe, too: if I can make killer mini bundts that look this good then anyone can.

Can you substitute the buttermilk?

Buttermilk is a great ingredient to have on hand, but unless you're an avid baker, you might not have any in the fridge when you come across a fun recipe.

However, you can make buttermilk at home with a few simple ingredients:

Add 1 tablespoon of lemon juice or vinegar to a liquid measuring cup.
Next, pour in milk, filling up to 1 full cup line, then stir.
Let the mixture sit for at least 5 minutes or until the mixture begins to curdle. Give the mixture a whisk to fully incorporate, then use in a recipe as directed.

If you need more than 1 cup, just adjust the amounts accordingly. For example, this recipe uses 2 1/2 cups, so you'd use 2 1/2 tablespoons of lemon juice or vinegar and then fill the measuring cup up with milk to 2 1/2 cups.

Looking for more ways to create buttermilk? Check out this article: 14 Great Substitutes for Buttermilk.

Top down view of 3 decorated Halloween cakes.

Can you freeze buttermilk cakes?

Yes, you totally can! However, it is highly recommended that you freeze these cakes prior to decorating and freeze them on the day of baking.

To freeze these cakes:

Bake per recipe instructions and allow cakes to cool to room temperature.
Wrap cakes in plastic wrap, then wrap them in aluminum foil.
Place wrapped cakes in a sealed container and store in the freezer for up to three months.

To thaw cakes:

For best results, allow cakes to thaw slowly in the refrigerator overnight or thaw on the kitchen counter for a few hours.

Can you freeze the red glaze?

These Halloween cakes come with a custom red glaze recipe, and unfortunately, I can't recommend freezing it. The texture will likely change upon thawing, making it too unappealing to eat.

Can you make these cakes in advance?

Yes, you totally can – but with a catch.

The frosting for this recipe is meant to be very fluid and liquid (so it resembles blood) and with the buttermilk cakes having such a spongy texture, they will slowly absorb the moisture or color of the frosting over time.

To avoid this, I'd recommend waiting to decorate the cakes until just before serving. If you can't decorate then, plan on decorating no more than four hours before serving to ensure these Halloween cakes still have the best presentation. I know this can complicate your plans, but you could also have fun with it, like allowing guests to decorate their own bundt cakes to create the perfect "murder scene."

How long do these Halloween cakes last?

Once prepared, these mini bundt cakes can be stored in a sealed container in the refrigerator for up to four to six days.

Close up of decorated killer Halloween mini bundt cake.

notes & tips for these Halloween bundt cakes

To make these cakes as pictured, you'll need two key pieces: this set of individual mini bundt cake pans (or 2x solid bundtlette pans) and Halloween knife decorations.

More fun Halloween recipes

How to make killer Halloween cakes

This next part is only a photo tutorial of the recipe steps. If you're looking for the full recipe measurements and instructions, scroll down to Recipe Details.

Step 1 – Start off by grabbing a medium bowl and whisking together the flour, baking powder, and salt. Set the bowl aside for now.

Step 2 – Using a stand mixer (or hand mixer + large bowl), whip together the butter and sugar until nice and smooth.

Step 3 – Add the eggs to the mixer, then mix for about one minute.

Step 4 – Slowly add the dry ingredients and the buttermilk to the batter (I did it in batches, alternating between dry and buttermilk). Also toss in the vanilla while you're at it. Mix until the batter is smooth and all ingredients are incorporated.

Step 5 – Spray a bundt pan (whether it be individual mini bundt pans or a solid bundtlette pan) with baking spray, then pour in the batter.

Step 6 – Bake!

Step 7 – While the bundt cakes bake and cool, prepare the red glaze by mixing together the powdered sugar, milk, red food coloring, and vanilla. Be sure to test the consistency, as the type of red food coloring you use may impact the texture of the icing. You want the icing to be solid yet still able to easily drizzle down the side of the cakes. If you need the frosting more liquid, add a dash of milk. If you need the frosting firmer, add more powdered sugar.

Step 8 – Once the bundt cakes are baked, crumble one up in a bowl. Drizzle some of the prepared red glaze on top, then use a fork to mix it up. Pick up a small piece and roll it into a tight ball. This will create the "brain matter" – it will sit in the center of the mini bundt cake so that the candy knife has something solid to stab into.

Step 9 – Decorate the bundt cakes by placing the "brain matter" in the center, drizzling it with red frosting, and spearing the center with a candy knife.

Step 10 – Serve and enjoy!

Recipe Details

Prepared killer Halloween cakes with red frosting and candy knives.

Killer Halloween Cakes

Yields: 9 mini bundts

These creepy (and easy!) Halloween cakes are perfect for any party! Spongy mini buttermilk bundts are drenched with red glaze and speared with candy knives.

Buttermilk Mini Bundts

1 cup unsalted butter, softened
5 egg, room temperature
1 1/2 cup buttermilk

Red Glaze

1 tablespoon milk
1 tablespoon red food coloring

For the Buttermilk Mini Bundts

Preheat oven to 325 degrees F. Spray mini bundt cake pans generously with baking spray, then set aside.
In a medium bowl, sift together flour, baking powder, and salt, then set aside.
Using a stand mixer (or hand mixer + large bowl), beat together butter and sugar on medium-high until fluffy and crumbly, about 2-3 minutes.
Drop mixer speed to low and add in eggs and vanilla, then mix until incorporated, about 1 minute.
Keeping speed on low, add about 1/3 of the dry ingredients to the batter. Next, follow with 1/2 of the buttermilk. Continue alternating between the dry ingredients and the buttermilk until all have been added and batter looks smooth with dry ingredients fully incorporated.
Pour batter into prepared mini bundt cake pans, filling each cavity about 3/4 to 4/5 full. This recipe typically makes enough for 9 complete mini bundts with a little a bit of batter left over. Go ahead and add the remaining batter to a 10th pan (can be any size the batter fits in) and bake it. The 10th cake will be crumbled and used to create the "brain matter" that helps keep the candy knives in place.
Place filled mini bundts pans on a baking sheet and bake for 20-30 minutes or until a toothpick tester comes out clean.
Let mini bundts cool (still in their pans) for 20 minutes, then remove mini bundt cakes from their pans and transfer to a wire cooling rack to cool completely.

For the Red Glaze

In a large bowl, whisk together powdered sugar, milk, vanilla, and red food coloring. If desired, add more red food coloring for a deeper color.
Check the consistency of the glaze; you may get different results depending on the type of food coloring used. You want the glaze to be thick enough that it's not too drippy but liquid enough that it will fall down the cake. If you'd like, test how the glaze falls on the 10th bundt cake you prepared (the one that will be used for crumbling). If you need a thinner glaze, add more milk, 1/2 teaspoon at a time. If you need the glaze thicker, add more powdered sugar, 1/4 cup at a time.

Putting it all together

Place your 10th bundt cake in a small bowl and crumble it into small pieces. Add about 1 tablespoon of the red glaze to the bowl and then thoroughly mix it with the cake crumbles. I like to call this the "brain matter."
Scoop up 1-2 tablespoon of the brain matter and roll it into a tight ball. Place the brain matter ball on the top indentation of the bundt cakes. Repeat this step for all the bundt cakes you have.
Using a pastry bag (or a Ziploc bag with a hole in the corner), drizzle the red glaze on top of the brain matter in the center of the mini bundts, then drizzle it down the grooves of the bundt.
Finish by placing a candy knife in the center of the bundt, securing it in the brain matter under the frosting.
Serve killer bundt cakes immediately.

I do my best to provide nutrition information, but please keep in mind that I'm not a certified nutritionist. Any nutritional information discussed or disclosed in this post should only be seen as my best amateur estimates of the correct values.