For the best custard filling in cream puffs, rule number one is to cook over low heat. It takes at least 20 to 25 minutes for the pastry cream to thicken, and raising the temperature to speed it up may cause the mixture to curdle.
Rule number two is to use a heavy saucepan, stir constantly, and practice patience for the perfect vanilla pastry cream filling.
Rule number three: Stirring continuously, making sure to cover the entire bottom and corners of the pan, helps prevent scorching and ensures an even heat distribution throughout the mixture.

INGREDIENTS
For the Pastry:
- 2 3/4 cups unbleached all-purpose flour
- 1/8 tsp salt
- 1/2 tsp baking soda
- 2 cups water
- 9 1/2 tbsp butter
- 6 large eggs
For the Custard:
- 1 cup sugar
- 1/2 cup flour
- 1/4 tsp salt
- 3 cups whole milk
- 4 egg yolks
- 3 tbsp unsalted butter
- 1 1/2 tsp vanilla extract
- 1 tbsp rum
DIRECTIONS
For the Pastry:
- Preheat the oven to 425°F and line a cookie sheet with parchment paper. Sift together the flour, salt, and baking soda, then set aside.
- In a heavy saucepan, heat the water and add the butter. Once the butter has melted, remove the pan from the heat and stir in the flour mixture all at once. Beat with a wooden spoon, then return the pan to medium-high heat, stirring until the dough pulls away from the sides of the pan.
- Remove the pan from the heat again, and add the eggs one at a time, beating well with a wooden spoon or hand mixer after each addition until fully incorporated.
- Transfer the batter to a pastry bag fitted with a ½-inch tip. Pipe 3-inch puffs about ½ inch apart onto the prepared cookie sheet.
- Bake for 20 minutes or until golden brown. Once done, carefully slit the side of each puff with a knife to allow steam to escape and prevent sogginess inside. Move the puffs to a cooling rack and let them cool completely.
For the Custard:
- In a saucepan over moderate heat, whisk together the sugar, flour, and salt. Gradually add the milk, cooking and stirring until the mixture thickens and starts to bubble.
- Reduce the heat and continue stirring for 2 minutes, then remove the pan from the heat. In a small bowl, gradually add a little of the hot cream mixture to the egg yolks, whisking constantly. Slowly pour the egg mixture back into the pan and bring it to a gentle boil. Cook for 2 more minutes, then add the butter, rum, and vanilla extract. Remove from the heat and transfer the custard to a shallow bowl to cool. Place plastic wrap directly on the surface of the custard to prevent a skin from forming. Refrigerate until completely chilled.
- Once the custard has cooled, pipe it into the opened pastry shells until they are full. Top with a cherry and dust with powdered sugar before serving. Enjoy!