Peanut butter base:
50g (2oz) dark brown sugar
200g (7oz) icing sugar
50g (2oz) unsalted butter, softened
200g (7oz) smooth peanut butter
200g (7oz) milk chocolate
100g (3 1/2oz) dark chocolate
decorations (I used edible glitter in a "Penny Copper" shade)
All you need to do is throw all of the peanut butter base ingredients into a food processor and blend until they reach a sandy consistency. Since it's so hot here right now, mine was more like a lumpy sand, but it still works fine.
Lay out 48 petit four cases into a mini-muffin pan, or somewhere you can line them up neatly and they won't slide around. Add one teaspoon of the peanut butter mixture and press down into each case. Depending on how generous your teaspoon is, you might end up with more or less cups. Also, you may find the irresistible urge to nibble on some of the peanut butter mixture, which can greatly reduce the number of peanut butter cups at the end.
Set up a saucepan with a small amount of water (maybe 3 inches in the bottom) simmering on a low-medium heat. Use a heatproof bowl suspended over the water to heat the chocolate gently. Make sure the bowl isn't touching the water, and stir the chocolate regularly so it melts slowly and doesn't burn. Once it's fully melted, spoon the chocolate on top of the peanut butter mixture and tap the tray gently to get a flat and even coverage. You can sprinkle with Cachou balls, (edible) glitter, or whatever fancy decoration you feel like. Refrigerate for about an hour and they're ready to go! Yum, yum.
The recipe I used here is by Nigella Lawson (in my own words).
Girl knows how to make a Christmas treat.