Foolproof Double Chocolate Eclairs Recipe (with Video)

Eclairs Preparation
1. Preheat oven to 400F and line 2 baking sheets with silicon baking mats.
2. Mix the butter, water, milk, sugar and salt in a nonstick saucepan. Place over medium low heat and stir constantly until the sugar and salt dissolve, the butter melts, and the mix just comes to a boil.
3. Remove from heat and dump in the flour (sifted). Stir rigorously with a wooden or rubber spatula for ~1 minute until all lumps are removed and a smooth ball forms. Place back on the heat and keep stirring for another ~1-2 minutes until the mixture dries out and the dough forms a thin film on the bottom of the pan.
4. Remove from heat and let cool for 5-10 minutes.
5. Break the eggs in a separate bowl and whisk to break them down.
6. Add the eggs slowly to the dough while whisking it using an electric beater. Do this until a thick batter forms which falls off the spatula in a V shape. Do not add any more eggs once this stage is reached.
7. Transfer the batter to a piping bag with a ½" french star tip. Use your palm to gently knock out any air from the batter.
8. Pipe 5" eclairs on the baking sheets, with no more than 6 on one. Apply steady pressure and flick off at the end as you release the pressure. Clean up the edges with a wet finger gently. Then, gently brush on egg wash.
9. Bake for 10 minutes at 400F, then drop the temperature to 330F without opening the oven, and bake for another 30 minutes. In the last 5 minutes, remove from the oven and make 3 holes on the bottom of each éclair using a Bismarck piping tip. Place the eclairs upside down and return to the oven for 5-8 minutes.
10. The eclairs should be golden brown and crispy. Remove from the oven.
Chocolate crème patisserie Preparation
1. Mix the milk and cream in a nonstick saucepan and bring to a boil. Separately, mix together the egg yolks, sugar, and cornstarch.
2. Pour ⅓ of the milk mixture into the egg mixture while whisking quickly, then pour back into the sauce pan while continuing to whisk.
3. Place onto low heat and keep stirring continuously while cooking for a few minutes. Remove from heat once a thick custard consistency is reached and the mixture coats the back of a spoon.
4. Pour the mixture over chopped chocolate in a heatproof bowl, and cover for 5 minutes. Then mix until a smooth chocolate crème patisserie is formed.
5. Let cool completely in the fridge, then transfer to a piping bag fit with a Bismarck piping tip.
Eclair Assembly
1. Once the shells and crème patisserie have cooled down, fill each éclair with the crème patisserie all the way. You know they are filled when you push the cream into one hole and it oozes out of the other.
2. Place upside down on a wire rack and transfer to the fridge.
3. Make the chocolate glaze by melting together the chocolate and butter over a double boiler. Let cool for 5-10 minutes.
4. Dip the top of each éclair in the chocolate glaze, shake off the excess and clean the edges with your fingers. Place onto a wire rack to catch any drippage as the glaze sets.
5. Serve and enjoy.