Begin by making the choux pastry, preheat the oven to 180C (160C Fan) Gas 4 and line two baking trays with baking parchment, draw 6 lines 14cm long, evenly spaced apart on each tray and turn the paper over so the lines are on the reverse.
Put the butter, salt, sugar and 120ml water in a medium pan over a medium-high heat. Once the butter has melted and the mixture is at a rolling boil, add the flour and quickly stir together with a wooden spoon until the mixture forms a dough.
With the pan still on a low heat, stir vigorously for 2 minutes, then tip the dough into a bowl and beat for a few minutes until it stops steaming. These two actions help to cook the flour and dry out the dough, which in turn helps it to absorb more egg. This helps the choux pastry to expand properly as it bakes.
Add the eggs, one at a time, beating until fully absorbed before adding the next. Depending on the flour used and how much water evaporated as you made the dough, the choux pastry will need varying amounts of egg, so the above is given as a guide.
With this recipe I usually add two eggs and then very slowly start adding the remaining egg, checking the texture of the dough after each addition. You are looking for a dough that has a shine and when it is lifted from the bowl, it should fall from the spatula in a ribbon that forms a "V" shape. If the dough doesn't contain enough egg, it won't expand properly and will be prone to cracking as it bakes; if there is too much egg, the dough won't hold its shape and will collapse as it bakes.
To prevent the dough from drying out and forming a skin, immediately put the dough into a piping bag with a 1.5cm plain round piping tip fitted.
Pipe lines of choux onto the prepared baking sheets, you want your eclairs to be pretty thin, the same width as the nozzle. They will puff up, if you make them too big you won't be able to make 12.
Brush the eclairs with egg and bake for 25-30 minutes until golden brown and crisp. Turn off the oven and leave the eclairs in the oven to cool for 30 minutes.
Remove the eclairs from the oven and leave them to cool before icing and filling them.
While the eclairs are cooking, make the filling. Whip the double cream to stiff peaks and add the vodka and baileys 25ml at a time. Taste and add more baileys and vodka if desired, I wouldn't recommend adding more than 50ml of each spirit though.
Place the cream in a piping bag with a thin nozzle fitted and place it in the fridge to set.
When the eclairs are cool, using a knife cut three small holes in the bottom of each eclair and fill the holes with the chilled cream.
To make the chocolate fondant icing, put the chocolate, butter and water in a bowl and melt it over a pan of gently boiling water. When the chocolate is melted sift in the fondant icing sugar and mix until combined. Make sure you make the chocolate fondant in a bowl that is big enough to fit the eclairs, as you will be dipping the eclairs in the glaze.
Make the white fondant by mixing the fondant icing sugar with the water, place it in a piping bag fitted with a very small piping nozzle 1-2mm.
Take the filled eclairs, dip them in the chocolate glaze and place them back on the wire rack. Dip a few eclairs at a time and then using the white fondant icing pipe stripes across the eclair. Using a cocktail stick, lightly drag it through the lines in one direction and then in the other direction to create a feathered look.
Do this with all of the eclairs, being careful not to leave it too long between coating and piping the stripes or the icing will set and the effect won't look as delicate.
Leave the eclairs to set and then store in an airtight container in the fridge. These will keep for a couple of days, but should ideally be eaten on the day they're made to stop the choux becoming too soft.