01 - Preheat oven to 400°F. Line a baking sheet with parchment paper.
02 - In a large bowl, whisk together the flour, sugar, baking powder, baking soda, and salt until well blended.
03 - Add the cold butter cubes to the flour mixture. Cut them in using a pastry cutter or your fingers until the mixture resembles coarse crumbs with some pea-sized butter pieces remaining.
04 - Stir the chocolate chips into the flour-butter mixture until evenly distributed.
05 - In a separate bowl, whisk together the heavy cream, egg, and vanilla extract until fully combined.
06 - Pour the wet ingredients into the dry ingredients. Gently mix with a fork until just combined and a shaggy dough forms. Do not overmix.
07 - Turn the dough onto a lightly floured surface. Gently pat into a 1-inch thick circle. Cut into 8 equal wedges and transfer to the prepared baking sheet, leaving space between each.
08 - Brush the tops with a little extra cream. Bake for 16–18 minutes until golden brown and a toothpick inserted comes out clean. Cool on a wire rack.
09 - Whisk powdered sugar, 2 tbsp milk or cream, and vanilla extract until smooth. Add additional liquid 1 tsp at a time if needed to reach desired consistency.
10 - Drizzle the glaze over cooled scones. Allow glaze to set for 10–15 minutes before serving.