Preheat oven to 400 degrees. In a small bowl, whisk together 3/4 cup of cream, molasses, and the egg. In a large bowl, whisk together the flour, granulated sugar, baking powder, ginger, cinnamon, salt, and cloves.
With a pastry blender, cut the butter into the flour mixture until it resembles coarse meal, with a few pea-size pieces of butter remaining. With a fork, stir in the cream mixture until just combined. The dough will still be crumbly.
Transfer the dough to a lightly floured work surface and pat into a 6-inch circle. Cut into 6 wedges and transfer to a parchment-lined baking sheet. Brush the tops with 1 tablespoon cream and sprinkle with granulated sugar. Transfer to the oven and bake until golden, 16 to 18 minutes, rotating the sheet pan halfway through. Allow to cool on the sheet pan for 5 minutes and then transfer to a wire rack to cool completely.
While the scones cool, whisk together the powdered sugar and eggnog until smooth. Drizzle the glaze over the scones. Allow the glaze to set, approximately 30 minutes, before serving.
Store in an airtight container for up to 48 hours. Best when served the same day.