Preheat your oven to 350°F (175°C).
Place the pie crust in a 9-inch pie dish and set aside.
In a medium saucepan, whisk together the milk, sugar, cornstarch, and salt over medium heat.
Continue stirring until the mixture thickens and bubbles, about 5-7 minutes.
Remove from heat and let it cool slightly.
In a separate bowl, whisk the eggs and vanilla extract.
Gradually blend the warm milk mixture into the eggs, stirring constantly.
Pour the custard mixture into the prepared pie crust.
Bake in the preheated oven for 30-35 minutes, until set.
Let it cool completely before serving. Top with fresh berries if desired.