In a large bowl, whisk together flour, baking powder, sugar, salt, cinnamon and cardamom.
Add the grated frozen butter into the flour mixture, and wokr it in with your fingertips until it resembles wet sand, see post above for visuals.
In a separate bowl mix together heavy cream, egg and vanilla. Add the wet ingredients and the chopped dates to the flour, and mix together until combined with a spatula or fork.
Turn the dough out onto a lightly floured surface, and pat it into an 8 inch circle. Cut the circle into 8 wedges, and place onto a parchment paper lined baking sheet. Place the sheet with the dough on it into the fridge to rest for 15 minutes.
While dough is resting, heat oven to 400 F (200C). Take scones out of the fridge, and brush the top of each with a little heavy cream, and sprinkle with some sugar. Bake for 20-25 minutes, until edges and top are a light golden brown.
Serve warm, either plain or with some clotted cream and/or jam.