Ingredients:

  • 1 cup (240ml) water
  • ½ cup (113g) unsalted butter, cut into cubes
  • ¼ teaspoon salt
  • 1 cup (120g) all-purpose flour
  • 4 large eggs, at room temperature
  • 2 cups (473ml) whole milk
  • ½ cup (100g) granulated sugar
  • ¼ cup (30g) cornstarch
  • ¼ teaspoon salt
  • 4 large egg yolks
  • 2 tablespoons (28g) unsalted butter
  • 1 teaspoon vanilla extract
  • 4 ounces (113g) semi-sweet chocolate, finely chopped
  • ½ cup (118ml) heavy cream
  • 1 tablespoon (14g) unsalted butter
  • 1 tablespoon light corn syrup

Instructions:

  1. Heat milk in a saucepan.
  2. Whisk together sugar, cornstarch, salt, and egg yolks in a separate bowl.
  3. Temper the egg mixture with hot milk, then return to the saucepan and cook until thickened.
  4. Stir in butter and vanilla extract.
  5. Transfer to a bowl, cover with plastic wrap (touching the surface to prevent a skin from forming), and chill.
  6. Combine water, butter, and salt in a saucepan and bring to a boil.
  7. Add flour all at once and stir vigorously until a dough forms and pulls away from the sides of the pan.
  8. Transfer the dough to a mixing bowl and let it cool slightly.
  9. Add eggs one at a time, mixing well after each addition, until the dough is smooth and glossy.
  10. Preheat oven to 400°F (200°C).
  11. Line a baking sheet with parchment paper.
  12. Transfer the choux pastry to a piping bag fitted with a large round tip.
  13. Pipe 4-inch (10cm) long strips onto the prepared baking sheet, leaving space between each.
  14. Bake for 15 minutes at 400°F (200°C), then reduce the temperature to 350°F (175°C) and bake for another 20-30 minutes, or until golden brown and firm.
  15. Turn off the oven, crack the door slightly, and let the éclairs cool in the oven for 30 minutes.
  16. Combine chocolate and heavy cream in a double boiler.
  17. Heat gently, stirring occasionally, until the chocolate is melted and smooth.
  18. Stir in butter and corn syrup until glossy.
  19. Let éclairs cool completely.
  20. Using a sharp knife or a piping tip, poke two or three holes in the bottom of each éclair.
  21. Fill the éclairs with pastry cream using a piping bag.
  22. Dip the tops of the filled éclairs in the chocolate glaze.
  23. Place the glazed éclairs on a wire rack to allow the glaze to set.
  24. Chill for at least 30 minutes before serving.