In a medium saucepan, add the water, butter and salt and heat over medium heat until the butter melts and the water begins to boil. Remove the pan from the heat and stir in all the flour, stirring vigorously with a wooden spoon until the flour absorbs all the water. Return the pan to the stove, on medium heat, and continue stirring for 2 to 5 minutes, until you get a smooth dough that releases from the sides of the pan. Stick a spoon on the dough and check if it holds. If not, cook for a little longer to lose some more moisture.
Immediately transfer the dough to the bowl of a standing mixer and stir at low speed for 30 seconds to release some of the moisture. Begin adding the eggs, a little at a time, beating until each addition is completely absorbed before adding the next. The dough should be shiny and with a malleable consistency that withstands the shape without droping too much. If you prefer, you can incorporate the eggs in the dough by hand, without using the mixer. Put the dough in a pastry bag equipped with a wide (round or star) mouthpiece and let it cool in the refrigerator for 20 to 30 minutes.
Preheat the oven to 190º C and line a baking tray with parchment paper. With the pastry bag, make the éclairs about 12 cm long and spaced apart. Bake for 30 to 40 minutes, or until golden, being careful not to open the oven door before 25 minutes. Remove from the oven and prick each one with a toothpick. Let it cool down completely over a grid and then open in half, lenghtwise, with a serrated knife.
Beat the cream with the powdered sugar until it’s consistent and fill the éclairs using a spoon or the pastry bag. Place the strawberries slices on top and cover with the top of the éclair. Sprinkle with powdered sugar.