It's my mum's Sacher Torte type. She was Viennese.
6 oz of SR flour, caster sugar,butter and 3 eggs. If you want it bigger 4 eggs and 8 oz of the other ingredients. They weigh the same as the eggs. A gleich gewiecht cake.
Also cocoa , tot of rum, 3 tablespoons water. Bar of Bournville to ice it. Apricot jam.
Cream butter and sugar, add eggs one at a time with 2 oz flour(sifted). Stir the eggs and flour in. Sift in cocoa and add rum and water.
Bake in tin whose bottom comes out so you can get it out later, medium oven, 175 electric? 45 minutes and check with skewer if done. Is done when skewer is clean.
Slice in half when cool and put jam in middle and all over top and sides. Melt chocolate and pour all over. Serve with whipped cream.