In a medium saucepan, whisk together sugar, cocoa powder, flour, and salt until well combined.

Gradually stir in the milk, then place the saucepan over medium heat. Cook, stirring constantly, until the mixture thickens and begins to bubble.

Remove from heat and whisk in the egg yolks, vanilla extract, and butter until smooth and velvety.

Pour the filling into the pre-baked pie crust, spreading it evenly.

Allow the pie to cool slightly, then refrigerate until fully set (at least 2–3 hours).

Slice, serve chilled, and enjoy every decadent bite.

Serving and Storage Tips