Coffee and Walnut Cake with Oil

Instructions:

1. Preheat the oven to 350°F (175°C). Grease two 8-inch round cake pans and line the bottoms with parchment paper.
2. Using an electric mixer, cream together the softened butter, neutral oil, and caster sugar until the mixture is pale and fluffy.
3. Beat in the eggs one at a time, ensuring each is fully incorporated to prevent the batter from curdling.
4. Sift the self-raising flour and baking powder directly into the wet ingredients.
5. Gently fold in the dissolved coffee (coffee granules mixed with hot water) and the vanilla extract.
6. Using a rubber spatula, fold in the finely chopped walnuts until just combined to avoid over-working the gluten.
7. Divide the batter evenly between the prepared pans and bake for 30 minutes or until a toothpick comes out clean.
8. Prepare the coffee buttercream by beating together the softened butter and powdered sugar, then stirring in the dissolved coffee and heavy cream.
9. Frost the cooled cake layers with the buttercream and garnish with crushed walnuts.