INGREDIENTS
Pastry
1 cup water
½ cup unsalted butter
⅓ tsp. salt
1¼ cup (5.25 oz.) flour
4 eggs
Chocolate Pastry Cream
2 cups whole milk
½ cup Dutch-process cocoa
½ cup sugar
¼ cup + 1 tbl. cornstarch
¼ tsp. salt
4 egg yolks
2 oz. unsweetened chocolate, chopped
1 tbl. unsalted butter
¼ tsp. vanilla extract
¼ tsp. almond extract
Ganache
4 oz. semi-sweet chocolate, chopped
1½ tsp. light corn syrup
½ cup heavy cream
INSTRUCTIONS
Preheat the oven to 425 degrees and line two pans with parchment.
Pastry
Combine the water, butter, and salt in a small saucepan. Cook over medium heat until the butter is melted and the mixture is boiling. Add the flour all at once and stir quickly until the mixture is smooth and thick- it should only 15-30 seconds of stirring. Remove from heat and allow to cool to under 125 degrees (about 10 minutes).
Transfer the cooled mixture to a mixer and add the eggs once at a time. After you add the last egg, continue beating for at least 2 minutes. The mixture should look smooth and shiny.
Transfer to a pastry bag with a plain ¾" tip. Pipe into 5" logs that are about ¾" wide. Bake for 15 minutes, then reduce the oven temperature to 350 degrees and bake an additional 25 minutes. Remove from the oven and cut a small slit in the side of each log. Return to the oven for 5 more minutes to allow any steam to escape. Remove from the oven and col to room temperature.
Chocolate Pastry Cream
Combine the milk and cocoa in a pan. Cook over medium heat until it just comes to a simmer. While the milk mixture is warming up, combine the sugar, cornstarch, and salt in a medium sized bowl. Whisk the egg yolks into the cornstarch mixture. When the milk is hot, gradually pour about ½ cup of the milk mixture into the egg yolks, stirring constantly until smooth. Pour the egg mixture back into the pot and stir until smooth. Cook over medium heat until the mixture becomes very thick.
Remove from the heat and add the chocolate and butter. Stir until smooth. Add the vanilla and almond extract and stir together. Press a piece of plastic wrap onto the surface of the filling, then refrigerate for at least 2 hours until cool.
Ganache
Combine the chopped chocolate and corn syrup in a bowl. Heat up the cream until it simmers, then pour it over the chocolate. Allow the chocolate mixture to sit for a minute, then gently stir to combine. Allow it to cool for about 5 minutes before using.
Assembly
Cut each eclair in half horizontally. Pipe the filling into the bottom half of each eclair shell. Dip the top half of the shell into the chocolate ganache, then place on top of the filled bottom shell.