Preheat your oven to 425°F and lightly grease a baking sheet.

In a medium bowl, whisk together all-purpose flour, baking powder, baking soda, salt, ground ginger, ground cinnamon, and ground cardamom.

Add cold butter into your dry mixture and toss to coat. Press the butter pieces into small flat pieces.

Fold in diced ginger, ensuring it's evenly distributed throughout the mixture.

In a small bowl, whisk together heavy cream and brown sugar until blended, then pour into the flour mixture and mix gently.

Transfer the dough to a lightly floured surface and fold it a few times to incorporate any dry bits.

Pat the dough into a circle about 1 inch thick and 7 inches across. Chill for 10-15 minutes if needed.

Cut the dough into eight wedges using a chef's knife, pressing down directly to preserve layers.

Arrange the cut scones on the baking sheet. Brush with egg wash and sprinkle with coarse sugar.

Bake for 18-22 minutes, rotating the pan after 14 minutes. They are done when they are light gold and firm to the touch.

Let them cool on a wire rack before serving. Store leftovers wrapped at room temperature for 2-3 days.