Preheat oven to 350°F (175°C). In a medium bowl, combine the gluten-free graham cracker crumbs, 6 tbsp melted butter, and ¼ cup granulated sugar. Mix well until crumbs are moistened. Press mixture firmly and evenly into the bottom and up the sides of a 9-inch pie plate.

Bake the crust for 8-10 minutes, or until lightly golden. Remove from oven and let cool completely.

In a large saucepan, whisk together 1½ cups whole milk, ¾ cup granulated sugar, ¼ cup cornstarch, and the 4 egg yolks until smooth. Cook over medium heat, whisking constantly, until the mixture thickens to a pudding-like consistency (about 5-8 minutes).

Remove from heat and stir in the 2 tbsp unsalted butter and 2 tsp vanilla extract until the butter is melted and incorporated. Stir in the 10 oz. melted semi-sweet chocolate until the filling is smooth and glossy.

Pour the chocolate filling into the cooled pie crust, spreading it evenly.

Chill the pie in the refrigerator for at least 4 hours, or until the filling is firm. Serve cold.