A few weeks ago, my niece Cindy sent me an email with an advertisement for a cake pan for making piñata cakes. I had never thought of making a pinata cake before, but decided that would be great for the cakes I was making for the twins’ fourth birthdays. However, I am more of an Alton Brown follower than one who would buy a special pan for a single use. I did buy the dome pan that was used in the cake decorating class to make the “Girl Cake” and hopefully I will find more uses for it. I had to figure out how to make the hollow center of the piñata cake using just what I have.
I decided that I could put a tin can in the center of a cake pan and that would create the cavity I needed for the piñata. Interesting enough, at this point I had to become an engineer and decide how much cake mix I needed for the layer of the cake with the hole in it. The tin can I had was 4 inches in diameter; I think that is known as a #2½. They are usually on the bottom shelf in the grocery store with tomatoes, and refried beans.
If you aren’t really interested in all this engineering and want to get directly to the making of the cake, skip down to that subtitle- MAKING THE CAKE.
I assumed that I would use the same rise in cake as I do for a normal layer. That meant I could compare the amount of batter I needed with the amount for a full 8 inch layer by comparing the area of the pans. The 8 inch layer pan would have an area of Pi R squared or 4 squared Pi or 16 pi. The area of the can would be 2 squared Pi or 4 Pi. That means the area I have to fill with batter is 16 – 4 Pi or 12 Pi. That is 3/4 of a single 8 inch layer.
Now normally I use 1½ boxes of cake mix to make 2- 8 inch layers; that means I use .75 of a box for a single layer or an area of 16 Pi. I should need ¾ of the .75 of a box- or 9/16 of a box. That is pretty close to the ½ box that I have left over from making the 2- 8 inch layers and so now I have a use for that leftover half box.
So, you need two slightly different recipes for the layers of the cake. I use the Duncan Hines cake mix and it says to use 3 eggs, 1 cup water and 1/3 cup vegetable oil for the box of cake mix. I first measure out the half box of cake mix by weight; 8.25 ounces. Now I increase the recipe to be 5 eggs, 1 ½ cups water and ½ cup vegetable oil. (one third cup is 2 sixths, and half of that would be one sixth for a total of 3 sixths which is ½.)
For the layer with the cavity, I use 2 eggs, ½ cup water and 2T + 2t vegetable oil. (1/4 cup is 4T and is also 3/12 cup; divide by 3 and 1/12 cup is 1 1/3 Tablespoons; 1/3 cup is 4/12 cup, and half that would be 2/12 cup of 2 2/3 Tablespoons; a Tablespoon is 3 teaspoons so we have 2T+2t of vegetable oil). I am certain that most people will let me do the math and just go with what I say. I hope that is most of the information you need.
I bake my cakes at 325 degrees F. This is slower than suggested on the cake mix package. I also have Magi-Cake strips that I put around the cake pans to slow the cooking of the outside edge of the layer even more, giving me fairly flat layers right out of the oven. The reason for mentioning this is that I test the doneness of the cake using a bamboo skewer and not the clock. I know that my normal time for an 8 inch layer is close to 45 minutes.
So, now the making of the cake. I started by making the standard 2- 8 inch layers; then after washing everything from making the two standard layers, I used the remaining ½ box of cake mix and made the layer with the cavity. After the batter was in the pan around the tin can in the center, I poured cold water into the can to a level just higher than the 2 inch edge of the cake pan; this would cause the center to cook slower and keep the cavity layer more level.
Once the skewer showed the cavity layer was completely cooked, I racked it for the 15 minutes the mix directions suggest. During this first cooling time, I took the can out of the cake so that the center could cool better.
While I tort only the top and bottom layer of the cake with glaze, I didn’t want to slice the cavity layer for fear it would break. I also wanted to have a sealing, non-sticky bottom to the cavity, so I used my crusting butter cream frosting between the top of the bottom layer and the cavity layer.
I took a break at that point to hopefully let the butter cream frosting in the bottom of the cavity to crust.
I filled the cavity with 7 ounces of Jelly Belly and M&M candies. This size cavity could probably hold 10 to 12 ounces of small candies without a problem.
Once the cavity was filled, I spread butter cream frosting on the top of the cavity layer and from there, the rest is like making any cake. There is one exception to being like any cake. Remember that this cake has an extra layer, making it tall; when I first got it together, it reminded me of the chocolate cakes you see at many cafes. And that means that it will require more frosting to cover.
I think you could easily make what would be a 2 layer pinata cake by doing the following. You could use only a single box of cake mix and follow the directions for adding the eggs, water and oil. When you are preparing your 8 inch cake pans, put the tin can that creates the cavity in one of the pans. Now, when you cook the batter, you will have one pan that is normal and one pan that has the cavity. Go ahead and cool the cake as normal.
Now comes the tricky part! Slice the normal layer in half, and you have a half layer for the bottom of the cake, and a half layer for the top of the cake. Frost the top of the bottom half layer and set the cavity layer on it. I think now you can finish your 2 layer pinata cake by filling the cavity and then frosting the top of the cavity layer and placing the top half layer in place.
My math says that the ideal size for the amount of batter would be 1.25 boxes; that would correspond to using 1.5 boxes for 2 normal 8 inch layers. But since the cake box people think one box is right for 2- 8 inch layers, then I would think you would get good rise with a single box of cake mix since you are not filling all of the 8 inch cake pans; you have the cavity-making can in one of the pans.
Next time I make a pinata cake, I will try using a single box of cake mix and let you know how it goes. Or if you should try it before I get there, send me a comment and let me know how it went.