Pre-heat oven to 400 degrees and line a baking sheet with parchment paper.
In a large bowl, whisk together flour, sugar, baking powder, cinnamon, ginger, allspice, cardamom, salt, and pepper.
Cut in butter with a pastry blender or fork (or your hands), until pea-size pieces form with some larger chunks remaining.
In a small bowl, whisk together cream and eggs. Using a spatula, fold the cream/egg mixture, grated carrots, and chopped walnuts into the dry mixture until just combined.
On a lightly floured surface, gently knead the dough a few times. Then using your hands, form a circle about ¾" thick. Slice dough into 8 triangles and place on prepared baking sheet. Brush scones lightly with heavy cream.
Bake for 13-16 minutes, until scones are just turning golden around edges.
Let scones cool before drizzling with chai cream cheese frosting and sprinkling with additional grated carrots and chopped walnuts.