1. Make the Custard:
Heat milk in a medium saucepan until simmering. In a separate bowl, whisk together sugar, cornstarch, and salt. Add egg yolks and whisk until smooth.
Slowly pour the hot milk into the egg mixture, whisking constantly. Return the mixture to the saucepan and cook over medium heat, stirring constantly, until thickened.
Remove from heat and stir in vanilla extract. Transfer custard to a bowl, cover with plastic wrap, and refrigerate until chilled.
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