Step 1: Preheat your oven to 350°F (175°C) and grease a 9×5 inch loaf pan or line it with parchment paper.
Step 2: In a medium bowl, combine the chopped dates and baking soda. Pour the boiling water over them and let soak for 15 minutes until softened.
Step 3: In a large mixing bowl, cream together the softened butter and brown sugar until the mixture is light and fluffy.
Step 4: Beat in the egg, followed by the vanilla extract, orange zest, and orange juice until well combined.
Step 5: In a separate bowl, whisk together the flour, ground cardamom, baking powder, and salt.
Step 6: Gradually add the dry ingredients to the wet ingredients, mixing until just combined. Do not overmix.
Step 7: Stir in the soaked date mixture (including the liquid) and the toasted walnuts.
Step 8: Pour the batter into the prepared loaf pan and smooth the surface with a spatula.
Step 9: Bake for 50-60 minutes, or until a toothpick inserted into the center comes out clean.
Step 10: Allow the loaf to cool in the pan for 10 minutes before transferring to a wire rack to cool completely.