Make the Pie Crust

1. Preheat Oven: Preheat your oven to 425°F (220°C).
2. Combine Dry Ingredients: In a mixing bowl, combine the flour and salt.
3. Cut in Butter: Add the cubed butter and use a pastry cutter or fork to mix until the mixture resembles coarse crumbs.
4. Add Ice Water: Gradually add ice water, mixing until the dough comes together.
5. Chill Dough: Wrap the dough in plastic wrap and refrigerate for at least 30 minutes.

Prepare and Bake the Crust

1. Roll Out Dough: On a floured surface, roll out the dough to fit a 9-inch pie pan.
2. Transfer to Pan: Carefully transfer the rolled dough to the pie pan and press it into place.
3. Prick the Bottom: Use a fork to prick the bottom of the crust to prevent bubbling.
4. Bake: Bake in the preheated oven for about 15 minutes, or until lightly golden.
5. Cool Completely: Remove from the oven and let the crust cool completely.

Make the Chocolate Filling

1. Combine Ingredients: In a mixing bowl, combine the cocoa powder, sugar, and softened butter.
2. Beat Until Smooth: Using an electric mixer, beat on medium speed until well combined and creamy.
3. Add Vanilla: Mix in the vanilla extract.
4. Incorporate Eggs: Add the eggs, one at a time, beating well after each addition until the filling is fluffy and light.

Assemble the Pie

1. Fill the Crust: Pour the chocolate filling into the cooled pie crust, smoothing the top with a spatula.
2. Chill: Refrigerate the pie for at least 3 hours, or until the filling is set.

Prepare the Whipped Cream Topping

1. Beat Cream: In a mixing bowl, beat the heavy whipping cream until soft peaks form.
2. Add Sugar and Vanilla: Gradually add the powdered sugar and vanilla extract, continuing to beat until stiff peaks form.

Serve the Pie

1. Top with Whipped Cream: Spread or pipe the whipped cream over the chilled pie.
2. Garnish: Optional: garnish with chocolate shavings or grated chocolate.
3. Slice and Enjoy: Cut into slices and serve chilled.