If you've got an electric mixer -- either a handheld one or a freestanding mixer -- this is very low effort indeed, but it is a real showstopper. There's something quite extraordinary about the greedy silence that falls over the table as you put these out. You can almost feel it.
The glitz is provided by their utter fantabulousness and the scattering of candy over the top. If you don't want to use a candy bar, of course, buy some upmarket honeycomb, or else scatter with some finely chopped pistachios. You will lose the sugary-glitter look, but you will still have brought to life an elegantly voluptuous creation.
Preheat the oven to 350°F.
Break up the chocolate and melt it with the butter in a bowl in the microwave or over a double boiler. Once it's melted, sit the bowl on a cold surface so that the chocolate cools.
Preferably in a freestanding mixer, beat the eggs and sugar until thick and pale and moussey, then gently fold in the flour, baking soda, and pinch of salt.
Fold in the slightly cooled chocolate and butter mixture and then divide among 8 ramekins or custard cups. Put in the oven to bake for 25 minutes.
Meanwhile, get on with the glaze by melting the chocolate and butter in a microwave (or double boiler), then whisk to form a smooth glossy mixture and spoon this over the cooked puddings.
Decorate with Butterfinger rubble: I just put the bars in a freezer bag, set to with a rolling pin, and strew over the top.