Salted Caramel Éclairs

Prepare the Choux Pastry

1. 1Preheat oven to 400°F (200°C). Line a baking sheet with parchment paper.
2. 2In a saucepan, combine water, butter, sugar, and salt. Bring to a boil over medium heat.
3. 3Remove from heat and stir in the flour all at once until a smooth dough forms.
4. 4Return to low heat and cook, stirring constantly, for 1-2 minutes until the dough pulls away from the sides of the pan.
5. 5Transfer the dough to a bowl of a stand mixer fitted with the paddle attachment. Let cool for 5 minutes.
6. 6Add eggs one at a time, beating well after each addition, scraping down the bowl as needed, until the dough is smooth and glossy.
7. 7Transfer the dough to a piping bag fitted with a large star tip. Pipe 4-inch long éclairs onto the prepared baking sheet, leaving space between them.
8. 8Bake for 15 minutes. Reduce oven temperature to 350°F (175°C) and bake for another 15-20 minutes, or until golden brown and crisp.
9. 9Turn off the oven, prop the door open slightly, and let the éclairs dry in the oven for 10 minutes.
10. 10Remove from oven and let cool completely on a wire rack.

Make the Salted Caramel Pastry Cream

1. 1In a saucepan, combine sugar and water. Cook over medium-high heat, without stirring, until it turns a deep amber caramel color.
2. 2Carefully pour the hot caramel into the warm heavy cream (it will bubble vigorously). Stir until smooth. If caramel hardens, gently reheat until melted.
3. 3In a separate bowl, whisk together egg yolks and cornstarch until smooth.
4. 4Slowly temper the egg yolk mixture by gradually whisking in about half of the warm caramel-cream mixture.
5. 5Pour the tempered egg mixture back into the saucepan with the remaining caramel-cream. Cook over medium heat, stirring constantly, until thickened.
6. 6Remove from heat. Stir in the cold butter, sea salt, until the butter is melted and the pastry cream is smooth. Strain through a fine-mesh sieve into a clean bowl.
7. 7Cover the surface of the pastry cream directly with plastic wrap to prevent a skin from forming. Chill completely.

Prepare the Caramel Glaze

1. 1In a saucepan, combine sugar and water. Cook over medium-high heat, without stirring, until it turns a deep amber caramel color.
2. 2Remove from heat and carefully stir in the warmed heavy cream and sea salt until smooth. Let cool slightly until thickened but still pourable.

Assemble the Éclairs

1. 1Cut each cooled éclair in half horizontally or poke a hole in the bottom and sides.
2. 2Fill a piping bag with the chilled salted caramel pastry cream. Pipe the cream into the bottom half of each éclair or generously fill through the holes.
3. 3Place the top half of the éclair over the filling.
4. 4Dip the top of each filled éclair into the caramel glaze, or drizzle the glaze over the top.
5. 5Immediately sprinkle with sea salt flakes.
6. 6Chill for at least 30 minutes before serving.