Preparation Steps

• In a medium saucepan, whisk together the granulated sugar, cornstarch, and salt. Gradually whisk in the whole milk until smooth.
• Heat the mixture over medium heat, stirring constantly, until it begins to thicken and simmer. Reduce heat to low.
• In a separate small bowl, lightly beat the egg yolks. Slowly temper the egg yolks by whisking about 1/2 cup of the hot milk mixture into the yolks. This prevents the eggs from scrambling.
• Pour the tempered egg yolk mixture back into the saucepan with the remaining milk mixture. Whisk constantly over low heat for 1-2 minutes, until the custard is thick enough to coat the back of a spoon.
• Remove the saucepan from the heat. Stir in the fresh lemon juice, lemon zest, unsalted butter pieces, and vanilla extract (if using) until the butter is completely melted and incorporated.
• Pour the custard into a clean bowl. Press plastic wrap directly onto the surface of the custard to prevent a skin from forming. Refrigerate for at least 3-4 hours, or preferably overnight, until thoroughly chilled and set.
• Serve chilled, either on its own or as a topping for fresh berries, pie, or tart shells.