This isn't as tough as it sounds - before tonight, I'd never made ganache. Now I feel a bit like an expert!
You need:
2 boxes of your favorite chocolate cake mix
Everything required to make a double batch of cake batter per the instructions
12 oz heavy cream
16 oz dark chocolate, chopped
16 oz white chocolate, chopped
1 cup sugar
2 Tbsp canned pumpkin puree
Liqueur of your choosing and/or vanilla extract
Pumpkin pie spice (Pampered Chef Cinnamon Plus)
Start by heating 4 oz of cream + 2 Tbsp pureed pumpkin over low heat in one saucepan, and 8 oz of cream in another saucepan.
Preheat the oven and mix up the cake batter. Divide it evenly across three 9" round cake pans. Bake.
While the cake is baking, finish the ganache. When the cream is almost at a boil, turn off the heat, and add the chocolate. Add 16 oz white chocolate to the pumpkin/cream mixture, along with a pinch of pumpkin pie spice. Add 16 oz dark chocolate and 1 cup sugar to the plain cream. Mix slowly and thoroughly, until the chocolate is completely melted, and the ganache is glossy and smooth.
When the ganache is smooth, add the vanilla and/or liqueur. I used high quality Mexican vanilla extract in the pumpkin ganache, and amaretto in the chocolate ganache...about 1 tsp each.
Note 1: If the ganache breaks (gets lumpy/grainy), cool it down, then slowly reheat it to around 90-100ºF. Use a hand mixer or immersion blender to smooth and emulsify it into a creamy consistency.
Note 2: You may have to play with the white chocolate/cream ratio in the pumpkin ganache. The pumpkin puree tends to make it resistant to set. Don't be afraid to add several more ounces of white chocolate if it seems too thin. I think the amounts above are very close to the final amounts I used.
Note 3: I wound up adding about a tablespoon of butter to the chocolate ganache to smooth it out. With proper technique, I don't think the butter is required, but it worked for me.
Don't forget about the cake. It's probably overdone by now if you paid too much attention to the mess on the stovetop.
Cool the cakes and ganache to room temperature. When the pumpkin ganache is cool, whip it using a powerful blender, hand mixer, or stand mixer with a whisk. Add a few drops each of red and yellow food coloring if you want a brighter orange color.
Put a thick layer of whipped pumpkin ganache on top of one cake round. Add another layer of cake, and top with more pumpkin ganache. Frost the whole thing lightly with chocolate ganache and refrigerate for 15 minutes. Don't worry about what it looks like with the first layer of chocolate ganache - you're just aiming to "seal" the crumbs into a thin layer of ganache. Once that layer has cooled and set, add more chocolate ganache, this time making it look nice and even.
Mine is topped with piped pumpkin ganache, white chocolate flakes, and a little pumpkin gourd I found at WalMart.
Pair with a pumpkin ale, of course!
Serve to your grateful spouse/significant other and collect the reward later...
