Do I have to use Kirsch?
No. Kirsch is traditional and gives that unmistakable Black Forest aroma, but you can skip it. For a non-alcoholic version, replace the Kirsch in the soak with more cherry juice (or cherry syrup) plus a splash of vanilla and a squeeze of lemon to keep it bright.
Can I use canned cherries?
Yes. Use canned sour cherries if you can find them. Drain them and reserve the juice for the soak. If you only have sweet cherries, add a little extra lemon juice to the filling for balance.
I am using fresh or frozen cherries. Where does the soak come from?
Great catch: the filling thickens the cherry juices, so you will not have much free liquid left for soaking. If you are using fresh or frozen cherries, plan to buy cherry juice (or make a quick cherry syrup) for the soak. See the Cherry Soak ingredients for options.
Why is my sponge dense?
Usually it is one of three things: under-whipped eggs, over-folding once the dry ingredients go in, or opening the oven door early. Whip until the mixture is pale and thick, fold gently, and let the cake set before you peek.
How do I keep whipped cream from melting or weeping?
Cold bowl, cold cream, and stabilization. This recipe uses gelatin. If you prefer not to use gelatin, you can stabilize with mascarpone (see ingredient notes). It will be slightly richer and a little less bouncy than gelatin-stabilized cream, but still sturdy enough for stacking.
Can I make this as a sheet cake?
Yes. Bake the sponge in a 9x13-inch pan at 350°F (175°C) for about 28 to 35 minutes, or until the top springs back and a tester comes out with a few moist crumbs. Cool completely, then either keep it in the pan (easy mode) or turn out and slice to layer. Soak, spread cherries and cream, then finish with chocolate shavings and cherries.
Can I use 9-inch pans?
Yes. The layers will be a bit thinner. Start checking a few minutes early and bake until the cake springs back and a tester comes out mostly clean.