To make the choux pastry put the cold water and butter in a pan and heat until it comes to a boil
Remove from the heat and tip the plain flour into the pan. Beat it with a wooden spoon until it's mixed in. Put it back on a medium heat and beat it in the pan for a few minutes
Pour the mixture into a bowl and beat it for a few minutes until it is luke warm instead of hot. Slowly add the eggs, bit by bit, and whisk in thoroughly between each addition
Put the mixture into a piping bag with a round nozzle. Pipe out 4 inch long lengths of the pastry onto a lined baking tray. Use a sharp wet knife to stop the flow of batter
Bake the éclairs on 200C/400F/Gas Mark 6 for 15 minutes, then reduce the temperature to 180C/350F/Gas Mark 4 for a further 20 minutes. Poke small holes into the ends of each éclair and bake for a further 5 minutes
Melt the dark chocolate and dip each éclair in it to coat the tops. Leave the chocolate to set
Then melt the peanut butter candy melts and pipe a zig zag pattern over the dark chocolate
Make the filling by whisking together the peanut butter, double cream, icing sugar, caramel extract and salt. Fill the éclairs with the mixture using a piping bag and a star nozzle