• 225 g/8 oz plain flour
• 50 g/2 oz cocoa powder
• 1 level teaspoon bicarbonate of soda
• ¼ teaspoon salt
• 275 g/10 oz castor sugar
• 100 g/4 oz quick-creaming margarine
• 1.5 dl/¼ pint buttermilk
• 2 large eggs

Sift the flour, cocoa powder, bicarbonate of soda and salt into a mixing basin. Add the sugar and the margarine cut in pieces. Pour in the buttermilk and add the eggs. Stir with a wooden spoon just to blend the ingredients, then beat very thoroughly for 1 minute to get a smooth soft mixture.

Turn the mixture into two greased and lined 19- to 20-cm (7½- to 8-in) sandwich tins and spread level. Place in the centre of a moderate oven (180°C., 350°F., Gas Mark 4) and bake for 30 minutes. When baked the cakes will be well risen and springy to the touch. Cool in the tins and then turn out. Sandwich the layers with buttercream or with chocolate fudge frosting.