Preheat your oven to 400°F (200°C). Line a baking sheet with parchment paper or lightly grease it to prevent sticking.
In a large mixing bowl, combine the all-purpose flour, granulated sugar, baking powder, baking soda, salt, cinnamon, ginger, nutmeg, and cardamom. Whisk these dry ingredients until they are well-blended.
Add the cold pieces of unsalted butter into the flour mixture. Using a pastry cutter or your fingers, incorporate the butter until the mixture resembles coarse crumbs with some pea-sized pieces remaining.
Pour in the buttermilk and vanilla extract, mixing gently until just combined. Fold in the diced pear carefully to avoid breaking it apart too much.
Turn the dough out onto a floured surface and gently knead it just until it holds together; be careful not to overwork it. Pat or roll it into a circle about ¾ inch thick, then cut into wedges or use a round cutter to shape individual scones.
Place the shaped scones onto your prepared baking sheet, brush with heavy cream, and bake for 18-20 minutes or until golden brown on top. While they cool slightly, prepare your glaze by whisking together confectioners' sugar, cinnamon, and enough heavy cream to reach desired consistency before drizzling over warm scones.