Step 1: Prepare the Pie Crust

• Preheat your oven to 350°F (175°C).
• Roll out the pie crust and press it into a 9-inch pie dish. Trim the edges and crimp as desired.
• Bake the pie crust for 10-12 minutes until lightly golden. Remove from the oven and let it cool.

Step 2: Make the Chocolate Filling

• In a medium saucepan, whisk together sugar, cocoa powder, flour, and salt.
• In a separate bowl, whisk egg yolks and milk until smooth. Gradually pour this into the saucepan, whisking constantly.
• Cook over medium heat, stirring continuously, until the mixture thickens and begins to boil (about 7-10 minutes).
• Remove from heat. Stir in butter and vanilla extract until completely blended.
• Pour the filling into the cooled pie crust.

Step 3: Make the Meringue (Optional)

• In a clean bowl, beat egg whites with an electric mixer until soft peaks form.
• Gradually add sugar, beating until stiff, glossy peaks form.
• Spread meringue over the warm filling, ensuring it touches the crust edges to seal.
• Bake at 350°F (175°C) for 10-12 minutes, or until the meringue is golden brown.

Step 4: Serve

• Allow the pie to cool to room temperature before slicing. For optimal texture, refrigerate for at least 2 hours before serving.

Variation:

For a dairy-free version, use plant-based milk and a butter substitute that suits your dietary needs.