• Preheat oven to 175C (350 F) and line one deep 7 inch cake tin.
• In a medium sized bowl, sift together flour, cocoa powder, baking powder, baking soda, salt and coffee. Whisk well to combine and set aside.
• In a large bowl, beat the butter until it is creamy using a hand/stand mixer. Gradually add the sugars and beat on low until the mixture is light, fluffy and has an almost mousse-like texture (the time it takes to do this will depend on your mixer).
• Whisk eggs with extract in a small bowl and gradually add to the butter and sugar mixture, mixing until it is well combined. Be careful not to over-mix.
• Add the flour mixture and buttermilk to the butter mixture, alternating between the two and starting and ending with the flour mixture. Mix to combine gently.
• Pour mixture into prepared tin and bake for 1 hour, or until it is springy to the touch and a tooth pick (when inserted) comes out clean.
• Leave the cake to cool for at least 15 minutes before inverting onto a cooling rack. Once completely cool, level the cake by cutting the top off and cut into layers.
• To assemble, place one layer on a cake plate, cover with buttercream and top with another layer. Repeat this process with the third layer and top with more buttercream and any desired decorations.

To make Peanut Butter Buttercream

• Cream butter with a hand/stand mixer until creamy. Add peanut butter and vanilla and mix until combined. Sift in icing sugar, 1 cup at a time and mix until it is light and fluffy and you have the desired consistency.