Preheat oven to 425°F (220°C). Line two baking sheets with parchment paper and set aside.

In a medium saucepan, combine water, butter, and salt. Bring to a rolling boil over medium-high heat, ensuring the butter is completely melted.

Remove from heat and add all the flour at once. Stir vigorously with a wooden spoon until the mixture forms a smooth ball and pulls away from the sides of the pan, about 1 minute.

Transfer the dough to a mixing bowl and let cool for 3-4 minutes until warm but not hot. Add eggs one at a time, beating well after each addition until fully incorporated and the dough is smooth and glossy. The dough should fall from the spoon in a thick V-shape.

Transfer dough to a piping bag fitted with a large round tip. Pipe 4-inch long logs onto prepared baking sheets, spacing them 2 inches apart. Smooth any peaks with a wet finger.

Bake at 425°F for 15 minutes, then reduce temperature to 375°F (190°C) and bake for another 20-25 minutes until deeply golden brown and crisp. Do not open the oven during the first 20 minutes. Remove and poke a small hole in each éclair to release steam.

For the rose water pastry cream: Heat milk in a saucepan until steaming. In a bowl, whisk together sugar, cornstarch, and egg yolks until smooth. Slowly pour hot milk into the egg mixture while whisking constantly.

Return the mixture to the saucepan and cook over medium heat, whisking constantly, until thickened and bubbling, about 3-4 minutes. Remove from heat and whisk in butter and rose water. Strain through a fine-mesh sieve into a bowl, press plastic wrap directly onto the surface, and refrigerate until completely cold, at least 2 hours.

Once choux shells are completely cool, use a serrated knife to slice each éclair in half horizontally. Transfer chilled pastry cream to a piping bag and pipe generously into the bottom halves. Replace the tops.

For the glaze: Whisk together powdered sugar, milk, and rose water until smooth. Add a tiny drop of pink food coloring if desired. Dip the top of each éclair into the glaze, let excess drip off, and place on a wire rack. Garnish with dried rose petals if using. Let glaze set for 15 minutes before serving.