Put the water and butter in a pot and cook until the butter is completely melted and the mixture is boiling. Add the flour all at once and stir with a wooden spoon until obtaining a dough that detaches from the pot. Take the mixture off the heat and set aside in a bowl. Using an beater, beat until the dough is cool, then add the eggs one by one, and mix until smooth.
For frying, heat oil in a deep pot. Fill a pastry bag with a star-shaped piping tip with the churro batter, or you can use a thick plastic bag a cut corner. Put 3 churros in the hot oil. Form them by squeezing the pastry bag and cutting them with a scissor. Fry until brown all around. Remove from the oil and put in a bowl with a paper towel. Sprinkle with powdered sugar.
For the strawberry sauce, put the strawberries with the cup of sugar and water in a small pot and bring to a boil. Then, using a food processor, mash the cooked strawberries and 4 fresh strawberries, and voilà! If you prefer a seedless sauce, you can strain it.
Serve the churros hot with the strawberry dipping sauce.