This recipe is to make a one-layer chocolate sponge cake base in a 9-inch cake pan. If you need a double layer (like in the photos), double the recipe and bake them separately in two 9-inch cake pans.
Chocolate cake
Mix dry ingredients - Take a glass bowl and add all dry ingredients: oat flour, cocoa powder, coconut sugar, psyllium husk (or ground flax seeds), and baking soda. Mix with a spatula or a spoon.
Add dairy-free milk and apple cider vinegar to the dry mix and stir until you get a smooth batter.
Add peanut butter and apple sauce and mix again.
Finally, add sparkling water and mix gently.
Line your cake pan with parchment paper and pour in the mixture. Try to make the top as even as you can.
Preheat the oven to 350 Fahrenheit (180 degrees Celsius) and bake for 30 minutes.
Before removing the chocolate cake from the baking pan, wait for it to cool down.
Chocolate frosting
Scoop out the creamy part of the canned coconut milk after it was chilled in the fridge for at least 2 days. Try to take as little from the watery part as possible.
Now, take your hand mixer and whip it for 1 minute.
Add ¼ cup of hot chocolate powder at a time and whip it until combined. 1 minute or so.
Frost your cake using a silicone icing spatula. To have a decadent frosted cake, you need to count on 1 can per layer and 2 cans for the sides.
Video
Notes
RE-TESTED RECIPE AS A REACTION TO COMMENTSAs we received some comments about the amount of baking soda, I re-tested the recipe with new baking soda and ACV amounts and also added apple sauce to make the cake moister.