Sugar free chocolate fudge cake recipe

There's been a Birthday girl in the house his week! And she requested chocolate Birthday cake. This couldn't be simpler really; it's just a Victoria sponge with cocoa powder and I made the icing from Holex sugar free chocolate as follows:
Ingredients

• For the cake: 6oz soft butter
• 4 1/2 oz fructose
• 3 beaten eggs
• 6 oz Self Raising flour
• 1 oz cocoa powder
• For the icing: 100gm bar sugar free chocolate
• 100mls double cream
• 2oz butter (optional)
  

Method

• Cream together the fructose and butter until creamy
• Whisk in the beaten eggs until you have a batter-type consistency
• Stir in the flour and cocoa powder and mix well
  
• Put into two round greased tins and bake for 22 minutes (that's in my fan oven) until risen
• Remove from oven, leave to cool for a while and turn onto a cooling rack
• Once the cake is cold make the icing:
• In a bain marie (a bowl over a pan of simmering water to me and you) melt the bar of sugar free chocolate (I find Plamil sugar free is the most successful, but didn't have any in the house so used Holex) with the double cream and add butter to stabilise it if you're worried the chocolate will separate.
• The secret is to let is SLOWLY melt; keep it over a gentle heat and be patient!
• Spread between the layers and over the top
• Make it a day or two in advance and by the time you eat it, it will be deliciously rich and fudgy.