Chocolate Ganache Layer Cake

No nuance here – this cake is all about chocolate on chocolate on chocolate. Four layers of dark and fudgy stick-to-your-fork chocolate cake with the silkiest chocolate ganache in between. This is the recipe I use for any celebration that calls for chocolate cake! Makes one four-layer 4×8 inch cake (serves 9-16).

Ingredients:

• For the chocolate cake:
  • 80 grams neutral oil, such as sunflower or vegetable
  • 100 grams full-fat sour cream, cold is fine
  • 1 large egg, cold is fine
  • 160 grams light or dark brown sugar
  • 1/2 teaspoon salt
  • 3/4 teaspoon baking soda
  • 45 grams dutch-processed cocoa
  • 110 grams all purpose flour
  • 10 grams cornstarch
  • 130 grams hot coffee (or 130 grams hot water & 2 teaspoons instant coffee)

• For the chocolate ganache:
  • 300 grams dark chocolate (60-70% cocoa solids), finely chopped
  • 300 grams heavy whipping cream
  • 20 grams (1 tablespoon) corn syrup, honey, or golden syrup (optional)
  • pinch of salt

Instructions:

1. Make the chocolate ganache: place the chocolate in a large heatproof bowl. Heat the heavy cream, salt, and syrup/honey in a small saucepan until the cream is starting to simmer with bubbles around the edges. Pour over the chocolate, making sure all of the chocolate is covered. Let sit for about five minutes, then mix well to ensure all of the chocolate has melted and the mixture is fully combined. Cover the bowl and then chill in the fridge for 1-2 hours, or until it has thickened up into a spreadable texture.
2. Make the cake:
   • Heat your oven to 320 Fahrenheit (160 Celsius). Line an 8×8 inch (20×20 cm) metal baking pan with parchment paper.
   • In a large bowl, whisk together the oil, sour cream, sugar, salt, and egg until combined.
   • Sift in the cocoa powder, cornstarch, baking soda and flour. Whisk together until almost fully combined – a few small streaks of flour are fine.
   • Add the hot coffee and slowly whisk together until you have a smooth, thin batter.
   • Pour into your prepared pan. Tap the pan on the counter to remove large bubbles and bake for 20-25 minutes, or until a toothpick comes out with moist crumbs attached but no raw batter. Don’t overbake or the cake will be dry.
   • Let the cake cool completely before assembling – if the cake is still warm, the ganache will melt and slide off. Cake layers can be frozen, tightly wrapped, and assembled up to a week later.
3. Assemble:
   • Once the cake has completely cooled, use a cake slicer or serrated knife to divide into two equal layers. You should now have two 8×8 inch (20×20 cm) squares. Slice each layer in half horizontally, creating four equal rectangles. You should now have four 4×8 inch (10×20 cm) cake layers.
   • Place the one layer on the cake stand or turntable, and top with a thick layer of ganache. Spread evenly over the cake layer. Top with another layer of cake and ganache, and repeat until you have four layers of cake and four layers of ganache. Frost the edges of the cake with the remaining ganache.
     • If at any point the cake is wobbly and you’re struggling with it, place it in the fridge for about 30 minutes to firm up.
     • For a perfectly smooth cake, do a crumb coat – spread a very thin layer of ganache on the outside of the cake and chill in the fridge for at least 30 minutes. This step traps any loose crumbs so they don’t interfere in the final layer. Once the crumb coat has set, spread a thicker layer of ganache and use an offset spatula to create any swirls or desired decorations.
   • Enjoy! Store the cake, tightly covered, in the fridge for up to 5 days. Cake slices can be frozen, tightly wrapped, for a month.

Notes:

• Pan size: You can also bake this cake in an 8 inch (20 cm) round cake pan, but the cake will be thicker and take longer to bake.
• Make ahead: The cake itself can be baked, sliced, and frozen, tightly wrapped, for up to two weeks ahead of time, or kept in the fridge for up to two days. The ganache can be stored in the fridge for a few days as well, but will need to warm up slightly so it can be spread – let it sit at room temperature for about an hour.
• Cocoa: The type of cocoa you use will greatly affect the flavor of the cake, so use the best quality you can. My favorites are Cacao Barry’s Extra Brute or Valrhona’s cocoa powder.
• Gluten free chocolate cake: To make this cake gluten-free,
  • Replace the all-purpose flour with an equal weight of a gluten free flour blend that contains xanthan gum.
  • Increase the coffee/hot water to 160 grams.
  • After mixing, let the batter rest for 15 minutes to allow the flour to hydrate.
  • Follow the rest of the recipe as usual.