Chocolate Eclairs adapted from Iron Whisk

75 g water
75 g milk
75 g butter
5 g sugar
3 g salt
100 g bread flour, sifted
150 g eggs (~3), room temperature and lightly beaten
Icing sugar, for dusting
Star tip (ideally about 1.5 cm in diameter with ~16 small teeth)

Chocolate Custard filling adapted from Bruno’s Kitchen

Chocolate Mixture
125 ml milk
40 g unsweetened cocoa powder
130 g dark chocolate 58  to 64%

Custard
500 ml milk
1/4 cup + 1 Tbsp (60g) granulated sugar
1 vanilla bean or vanilla extract
100 g (~5) egg yolks
1/4 cup + 1 Tbsp (60g) granulated sugar
40 g cornstarch

Royal Icing Glaze
1 egg white
150g icing sugar
1/2 teaspoon vanilla extract
1-2 tsp milk to adjust consistency
Gel food colouring

To prepare the choux paste:

Bring the water, milk, butter, sugar, and salt to a strong simmer in a medium saucepan over medium heat. Remove the pot from the heat and add all the flour at once. Stir vigorously until the flour is completely incorporated. Return to heat and mix the dough, being careful not to scrape the bottom of the pan as a film may form there while cooking. Cook until the dough reaches 75°C (170°F), about two minutes. You may see a film form at the bottom of the pan. Transfer the dough to a bowl and, using a stand mixer fitted with the paddle attachment, mix on the lowest speed for about one minute and thirty seconds, such that the dough cools down to 60°C (140°F). You can also do this with a spoon or a hand mixer. Add half of the eggs and mix, still on the lowest speed if using a stand mixer, until combined. With the mixer still running, or your hand still stirring, add the rest of the beaten eggs slowly while you continue to mix. Once incorporated, mix for an additional minute until the dough is smooth.

To pipe & bake éclairs

Prepare a parchment paper lined baking sheet by dabbing a bit of choux between the paper and the pan at each corner to secure the paper to the pan. Transfer the choux to a pastry bag fitted with a star tip.

Pipe the éclairs in 13cm (5 inch) lengths, and about 2.5cm (1 inch) wide, at about a 45° angle between the bag and the parchment paper-lined baking sheet. Space the éclairs about 5cm (2 inches) apart. If needed, mark lines with a pen or pencil on the parchment paper to ensure the éclairs are equal in length. Dust with icing sugar.

Bake in a preheated oven at 180°C (350°F) for forty minutes, or until slightly darker than a golden brown. Remove from the oven and make a thin slit at the bottom of each éclair while still hot to let the steam escape. Let cool completely before filling and glazing.

To make Chocolate Custard filling

Make this the night before. Prepare chocolate mixture by bringing milk to boil and turn off the heat. Mix in chopped chocolate till smooth

Prepare custard. Bring milk, sugar and vanilla to a boil. Meanwhile, beat egg yolks and sugar and add cornstarch. When the milk boils remove from heat and temper the yolk mixture with one-third of the hot milk whisking constantly. Pour the tempered mixture into the saucepan and return to the heat.

Bring to boil and cook for 2 minutes whisking swiftly on medium heat. Remove from the stove and mix in the chocolate mixture. Press through a fine mesh-sieve and cool down completely, cover with plastic wrap in contact to prevent a skin from forming. Push off the vanilla pod and let dry. Save for later use. Once completely chilled, whisk the chocolate custard until smooth.

To make royal icing glaze and assemble

In the bowl of a stand mixer, beat egg whites on medium-low speed until frothy, about 1 minute. Slowly add in icing sugar and vanilla. Once fully incorporated, increase speed to medium-high and beat until stiff shiny peaks form.

Divide icing among small bowls, and dye with gel food coloring. Create marbling effect using the technique here. Dip each eclair into the marble icing. Store eclairs refrigerated up to 3 days