Ingredients:

  • 1 cup (240ml) water
  • 1/2 cup (113g) unsalted butter, cut into cubes
  • 1/4 teaspoon salt
  • 1 cup (120g) all-purpose flour
  • 4 large eggs
  • 2 cups (473ml) whole milk
  • 1/2 cup (100g) granulated sugar
  • 1/4 cup (30g) cornstarch
  • 1/4 teaspoon salt
  • 4 large egg yolks
  • 2 tablespoons (28g) unsalted butter
  • 1 teaspoon vanilla extract
  • 8 ounces (225g) semi-sweet chocolate, finely chopped
  • 1 cup (240ml) heavy cream

Instructions:

  1. Combine water, butter, and salt in a saucepan and bring to a boil. Add flour all at once and stir vigorously until a smooth dough forms and pulls away from the sides of the pan.
  2. Transfer dough to a mixing bowl and let it cool slightly (about 5 minutes) to prevent cooking the eggs.
  3. Beat in eggs one at a time, ensuring each is fully incorporated before adding the next. The dough should be smooth and pipeable.
  4. Transfer the dough to a piping bag. Pipe 4-inch long strips onto a prepared baking sheet.
  5. Bake in a preheated oven (375°F/190°C) for 30-35 minutes, or until golden brown and puffed up. Reduce the oven temperature to 325°F (160°C) during the last 10 minutes of baking if the éclairs are browning too quickly.
  6. Let éclairs cool completely on a wire rack.
  7. Whisk together milk, sugar, cornstarch, salt, and egg yolks in a saucepan. Cook over medium heat, stirring constantly, until thickened. Remove from heat and stir in butter and vanilla.
  8. Transfer the filling to a bowl, cover with plastic wrap (pressing it directly onto the surface to prevent a skin from forming), and chill in the refrigerator for at least 30 minutes.
  9. Place chopped chocolate in a heat-proof bowl. Heat heavy cream in a saucepan until simmering. Pour hot cream over chocolate and let sit for 1 minute, then whisk until smooth.
  10. Cut the cooled éclairs in half horizontally. Fill with the chilled vanilla cream.
  11. Dip the top half of each éclair into the chocolate ganache.
  12. Chill the assembled éclairs for at least 15 minutes before serving to allow the ganache to set.