Filling for Chocolate Fudge Cake

Our answer

As you mention, the filling for any cake can be tweaked to your own taste. However it is not clear if the jam is supposed to be on its own as a filling in the Chocolate Fudge Cake (from Nigella Bites) or in addition to the buttercream.

If you are using jam as an alternative to the buttercream, you may like instead to combine it with a ganache filling and you would need 100g/4 ounces dark (bittersweet) chocolate and 100ml/7 tablespoons double (heavy cream). Carefully melt the chocolate with the cream, stirring regularly, either in short bursts in a microwave or over (but not in) a saucepan of warm water. Let the ganache cool and thicken slightly before using. Spread the jam over the base layer of the cake and then carefully spread over the ganache. Add the top layer and cover the cake with the buttercream; you will need 3/4 of the buttercream amount in the recipe or just cover generously with the full amount!

You could also, if you prefer, use the jam in addition to the buttercream. In both cases we would suggest that you use a smooth jam and you can warm the apricot jam gently, then sieve (strain) it to remove any bits. As well as apricot jam, raspberry or cherry would be good flavours to try.