Preheat the oven at 350°F.
Grease a 9 inches round baking pan.
In a bowl mix sugar, flour, baking powder, baking soda and salt.
Add the sour cream, the oil, the egg and the vanilla extract.
Beating quickly by hand or with a food processor add slowly the hot coffee ( or water).
Pour the batter in the baking tin and bake for about 30- 35 minutes.
For the frosting: in a big bowl, using an electric mixer, combine butter ad cocoa.
Slowly add milk and icing sugar until you have the right spreadable consistency.
Add the golden syrup and the vanilla extract, mix well and let sit for at least ten minutes.
You can store in fridge, covered with cling film, for a couple of days; cold it has the texture of chocolate mousse and it's wonderful by the spoon: I suppose you are going to discover it by yourself.
Spread a generous amount of frosting on the cake when it's completely cold.
Melt chocolate with butter in a saucepan, mix until you have a smooth and shiny cream.
In a bowl beat sugar and yolks until foamy and pale yellow, add sifted flour and cocoa, mix then add chocolate.
In a separate bowl whip egg whites with a pinch of salt, when they form peaks add them to the chocolate mixture folding gently.
Pour the mixture into six well buttered alluminium ramekins, bake 8 minutes (no more, no less, except if you see your oven needs different timing) at 428°F.
Oven has to already be at the right temperature, no less.
Take the ramekins out from the oven, let them settle 2 minutes then take them out of the ramekin.
If you need an extra help to take them out cut the edge of the ramekin and "peel" the cake from the mould.
Put lava cake on plates with a spoonful of whipped cream or vanilla ice cream and serve immediately.
Beat sugar with butter untill fluffy, add cocoa and mix well.
Add biscuits roughly crushed and mix again adding beer enough to hve a mixture that stick together when pressed.
Pour the mixture on a tin foil, give it the shape of a salami and close the foil rolling this a little on a plain sourface to round it a bit.
Store in fridge at least two hours before serving sliced.
Whipped cream is not mandatory but highly recommended 😀