Eclair Custard Filling Recipe

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Eclair custard filling recipe is made with a vanilla bean infused into custard to create vanilla bean custard.

The vanilla beans are extracted from the pod, and added to the custard to make the vanilla custard flavorful throughout.

The vanilla pod is cooked into the milk letting the vanilla juices infuse the milk with vanilla flavor. The vanilla pod is removed after a couple of minutes prior to making the custard.

If you don’t have any vanilla beans, you can substitute vanilla bean paste (1 tbsp), or vanilla extract (2 tsp).

It’s best to add vanilla bean paste or vanilla extract at the end of the cooking process when the custard is cooling down.

Éclair Custard Filling Recipe

What can eclairs be filled other than custard

  • diplomat cream (pastry cream with added whipped cream)
  • Chantilly cream (whipped cream base with flavors added to it)
  • mousse

If you want to fill your eclairs with something a little more fancy, try out our eclair filling ideas.

How do you fill eclairs with custard

You can fill eclairs 2 different ways.

Cutting the Eclair in half and Filling it

  1. Cut the freshly baked éclair in half lengthwise with a serrated knife.
  2. Fill a piping bag with custard fitted with a 1/2″ round tip.
  3. Pipe the custard in one smooth motion – filling the éclair about 1/2″ thick with custard. Another option is to pipe circles of custard for a little bit of a different look to the éclair.
  4. Dip the top of the éclair in the glaze.
  5. Serve.

How to Pipe Custard into Eclairs

  1. Fit a piping bag with a 1/2″ round tip.
  2. Fill the piping bag with custard.
  3. Holding the metal tip, pierce the bottom of the éclair 3 times – 1 at either end, and 1 in the middle. You should have 3 circles piercing the bottom of the éclair.
  4. Press your piping tip into the circles you made and fill the éclair until it starts oozing out.
  5. Fill the eclair in the same way in the other 2 holes.
  6. Wipe the bottom of the excess custard off of the eclair using a paper towel.
  7. Dip the top of the éclair in the glaze.
  8. Serve
eclair filling recipe custard

When should you fill eclairs

You should fill eclairs just before serving.

The eclairs themselves should be baked the same day that you fill and prepare them.

The longer the éclair sits with the filling, the more soggy the pastry will get.

If your eclairs have been sitting awhile, pop them in the oven for a couple of minutes to crisp them up before serving.

When should you fill éclairs

Eclair Custard Filling Recipe

How to make an eclair custard filling
Prep Time10 minutes
Active Time40 minutes
Chilling time2 hours
Total Time2 hours 50 minutes
Course: Dessert
Keyword: dessert
Yield: 2 cups


  • 1 vanilla bean
  • 6 egg yolks
  • 2/3 cup sugar granulated
  • 1/4 cup cornstarch
  • 1 tbsp butter unsalted
  • 2 cups milk


  • Place milk in a medium saucepan on low-medium heat.
  • Cut the vanilla bean in half lengthwise with a sharp knife. Remove the vanilla beans and place them in the milk. Place the whole vanilla bean in the milk.
  • Let the milk just come to a simmer, not boiling. Turn off the heat source and remove the milk from the heat. Let the vanilla bean infuse flavor for 15 minutes.
  • In the meantime, separate your eggs. Place the egg yolks in a large heat proof bowl.
  • Add sugar and cornstarch to the egg yolks and mix together with a whisk.
  • Remove the vanilla bean from the saucepan. Slowly temper the eggs by adding a couple of tablespoons of the milk to the eggs at a time and vigorously whisking it until fully emulsified.
  • Continue adding the milk very slowly until fully combined. You do not want to cook the eggs.
  • Strain the mixture back into the saucepan and heat on medium heat.
  • Whisk the mixture frequently. Heat the mixture until the cornstarch has activated. It should be a few minutes. You will feel the mixture becoming thickened with your whisk.
  • Cook for 1 more minute after it has started to thicken.
  • Remove the eclair custard from the heat and add the butter. Whisk the butter has fully melted into the custard.
  • Let the custard cool until the pot can go in the fridge. Place a plastic wrap on top of the custard to prevent a film from forming.
  • Chill the eclair custard for 2 hours before using.