Adjust an oven rack to the lower middle position. Preheat the oven to 400°F. Stack two baking sheets on top of each other and line the top sheet with parchment paper.

In a large bowl, whisk the flour, baking powder, 2 tablespoons sugar, and salt. In a medium bowl or liquid measuring cup, whisk the crème fraîche, vanilla, and egg.

Add the butter to the dry ingredients and use a pastry cutter to cut it into the mixture until the flour-coated pieces are the size of peas. Stir in the crystallized ginger and the chocolate. Add the wet ingredients and fold with a spatula until just combined. (If your dough is on the dry side, you can add 1 tablespoon of heavy cream at a time until it comes together.)

Transfer the dough to a lightly floured surface and knead until it comes together, 4 to 6 times, adding flour as necessary, as the dough will be sticky. Pat the dough gently into a square and roll it into a 12-inch square (again, using flour as necessary). Fold the dough in thirds, similar to a business letter. Fold the dough into thirds again, making a square. Transfer it to a floured sheet pan or plate and put it in the freezer for 10 minutes.

Return the dough to the floured surface, roll it into an 8-inch square, about 1-inch thick. Use a biscuit cutter (I used a 2-inch cutter here to make smaller scones, but you can use a larger one) to cut out circles. Gently re-roll scraps as necessary. Transfer the scones to the prepared baking sheet.

Brush the tops with a little heavy cream, making sure it doesn’t drip down the sides and sprinkle the tops generously with sugar. Bake 15 to 25 minutes (smaller scones will bake faster), rotating the pan halfway through, until the tops and bottoms are light golden brown. Transfer the sheet pan to a wire rack and let the scones cool 10 minutes before serving.