In a large bowl, sift together the flour, cocoa powder, sugar, salt, and baking powder.
3
Cut the cold butter into cubes and work it into the flour mixture using a pastry blender or your fingertips until the texture resembles pea-sized pieces.
4
Fold in the chocolate chips and mix gently.
5
Add the cold heavy cream and mix with a spatula or fork until a shaggy dough forms. Add additional cream as needed until the dough holds together but remains rough in texture.
6
Turn the dough onto a lightly floured surface and shape it into a rectangle. Fold and stack the dough in half twice, pressing into a rectangle each time to create layers. Finally, press the dough into a 7-inch disc.
7
Cut the disc into eight roughly equal wedges.
8
Place the wedges on a parchment-lined baking sheet, spacing them about 2 inches apart. Refrigerate for at least 15 minutes.
9
Bake for 18 to 20 minutes until the scones are puffed and the centers are dry. Rotate the pan halfway through baking.
10
Once the scones have cooled, prepare the chocolate glaze by whisking together powdered sugar, cocoa powder, milk, and vanilla extract in a small bowl until smooth. Add more milk if needed to reach the desired consistency.
11
Drizzle the glaze over the scones or dip them in the glaze for full coverage. Finish with flaked sea salt if desired.