Preheat oven to 200C
Place water, milk, salt, butter and place it on medium heat until butter is melted
Add in the flour and mix well until it forms a ball. keep it on a low fire until the moisture has evaporated or until the dough forms sort of a ball and pulls away from the sides of the saucepan
Remove from the heat. Add in the dough onto a stand mixer with the paddle attachment
Mix on high heat. Add in the eggs little by little, making sure each is combined before adding the next. The Dough should be like a thick paste. (The egg quantity will vary from person to person, therefore you need to make a calculated guess when adding the eggs. If adding the last egg is too much then whisk it and add half of the egg)
Place dough into a piping bag fitted with a 13 - 15mm round nozzle
Line a baking tray with baking paper. Pipe long shaped eclairs
Brush the egg wash on top of the eclairs
Bake in the oven for 25-30 minutes
Take it out of the oven and let it cool down on a cooling rack