Ingredients:

  • 1 cup (240 ml) water
  • ½ cup (113g) unsalted butter, cut into cubes
  • ¼ teaspoon salt
  • 1 cup (120g) all-purpose flour, sifted
  • 4 large eggs
  • 2 cups (480 ml) 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 (120 ml) heavy cream

Instructions:

  1. Combine water, butter, and salt in a saucepan. Bring to a boil.
  2. Remove from heat and add flour. Stir vigorously until a smooth dough forms.
  3. Return to low heat and cook, stirring constantly, for 1-2 minutes to dry the dough slightly.
  4. Transfer to a mixing bowl and let cool slightly (5 minutes).
  5. Add eggs one at a time, mixing well after each addition, until the dough is smooth and glossy.
  6. Transfer dough to a piping bag fitted with a star tip.
  7. Preheat oven to 400°F (200°C). Line baking sheets with parchment paper.
  8. Pipe éclairs onto prepared baking sheets, about 4 inches long and 1 inch wide, spacing them evenly.
  9. Bake for 15 minutes, then reduce oven temperature to 350°F (175°C) and bake for another 20-25 minutes, or until golden brown and puffed.
  10. Turn off the oven and crack the oven door open slightly. Let éclairs cool in the oven for 30 minutes. (This helps prevent them from collapsing).
  11. Transfer éclairs to a wire rack to cool completely.
  12. Heat milk in a saucepan until simmering.
  13. In a separate bowl, whisk together sugar, cornstarch, salt, and egg yolks.
  14. Gradually whisk a small amount of the hot milk into the egg yolk mixture to temper it.
  15. Pour the tempered egg yolk mixture into the saucepan with the remaining milk.
  16. Cook over medium heat, whisking constantly, until the pastry cream thickens and comes to a boil.
  17. Remove from heat and stir in butter and vanilla extract.
  18. Pour into a bowl, cover with plastic wrap (pressing directly onto the surface to prevent a skin from forming), and refrigerate until chilled.
  19. Place chopped chocolate in a heatproof bowl.
  20. Heat heavy cream in a saucepan until simmering.
  21. Pour hot cream over chocolate and let sit for 1 minute.
  22. Whisk until smooth and glossy.
  23. Using a small serrated knife, cut a slit lengthwise in the bottom of each éclair.
  24. Fill each éclair with pastry cream using a piping bag or spoon.
  25. Dip the top of each éclair into the chocolate ganache.
  26. Refrigerate for at least 30 minutes to allow the ganache to set.