Tales of a Tiered Cake #2 – The Filling

I guess at this point I should tell you what my plans are for the cake. The bottom tier is going to be a chocolate cake with cherry filling and some kind of white buttercream – I’m thinking that kirsch or other cherry flavoring would be nice, but I haven’t decided on that yet. The upper tiers will have yellow cake with the same filling and buttercream.

To figure out how much filling I need, I have to figure out the area of each cake and then I can adapt my recipe accordingly. If you don’t know how to do this, the formula is:
Pi multiplied by the radius squared, or Πr²
The radius is half of the diameter, so if you have a 12-inch round pan, the radius is half of that, or 6. Pi = 3.14159
For my purposes, I always just round that to 3. So for my area here is my formula:
12-inch layer
6x6 (radius²) x 3 (pi) = 108
9-inch layer
4.5x4.5 x 3 = 61 (rounded)
6-inch layer
3x3 x 3 = 27

You can also use this formula if you want to make a cake that is bigger or smaller than the recipe you have.
I need to start with the filling because it takes time to marinate. I'll be using a marinated cherry filling that I've adapted from my CD-rom, Amazing Passover Desserts. For this cake I'll be adding some dried tart cherries to the original recipe and also I'll be chopping them in the processor, rather than leaving them whole. For the engagement cake, I think this will make a more uniform layer and will look nicer in the cake. The dried cherries, which I couldn't use for Passover (not kosher), add a depth of flavor that is truly wonderful, plus they have a little more tooth than the frozen cherries, as well. Oh, I should mention that I've never made this particular version before and am only guessing that it will work well in the cake. I'll have to report back after we taste it!
Sweet and Tart Cherry Filling
4 pounds frozen sweet cherries
1/2 cup Manischewitz™ Blackberry wine
2 cups sugar
1/2 cup orange juice
1/2 teaspoon cinnamon
1 cup dried tart cherries
2-4 tablespoons cornstarch

Defrost the cherries in a colander, over a bowl, and reserve the juice. Transfer the juice to a medium pot. You should have about 3 cups juice (press on the cherries to extract more of the juice). Add the wine, and simmer until the mixture is reduced by half. Add the sugar and orange juice. Stir until the sugar dissolves. Stir in the cinnamon and the dried cherries. Transfer the mixture to a storage container, and refrigerate for at least 2 days and up to 2 weeks. As the defrosted cherries marinate, they will actually get firmer and tastier, while the dried cherries will get softer and plumper.

When ready to use the cherries, place the cornstarch in a small bowl. Gradually stir in 1/4 to 1/2 cup of the cherry juice (use 2 TB cornstarch for a lightly thickened mixture and 4 tablespoons for a very thick, gelled topping or filling). Place the remaining cherries and juice in a large pot. Bring to a simmer and stir in the cornstarch mixture. The mixture will look cloudy. Cook until the mixture thickens and becomes translucent. Remove from the heat and let cool. Refrigerate until ready to use.