0 In a medium saucepan, whisk together the sugar and cornstarch. Mix in the egg yolks, vanilla bean paste, and salt until well combined. Continue whisking until the mixture lightens in color.
1 Slowly stream the milk into the egg mixture while continually whisking, to prevent any lumps from forming.
2 Cook the mixture over low heat, whisking constantly while the mixture thickens and starts to boil, about 10-15 minutes. Do not walk away from the pastry cream while it’s cooking.
3 Allow the mixture to boil vigorously, forming large popping bubbles on the surface. Boil for about 10 seconds to properly thicken the pastry cream, then remove it from the heat.
4 Strain through a fine-mesh sieve, then stir in the butter.
5 Place plastic wrap directly on top of the custard to prevent a skin from forming. Chill in the fridge until completely cooled.
6 When ready to use, whisk up the pastry cream to make it smooth and creamy again. Add it to pastries, tarts, or cakes, and enjoy!
