Step 1: Preheat your oven to 350°F (175°C) and grease a 9-inch square baking pan or individual ramekins.
Step 2: Place the chopped dates and baking soda in a heatproof bowl. Pour the boiling water over them and let stand for 15 minutes to soften.
Step 3: In a large mixing bowl, cream together the softened butter and dark brown sugar until light and fluffy.
Step 4: Beat in the eggs one at a time, then stir in the orange zest and orange juice.
Step 5: Sift the self-rising flour, cinnamon, ginger, and salt into the wet mixture. Fold gently until just combined.
Step 6: Stir in the date mixture (including the soaking liquid) until the batter is uniform.
Step 7: Pour the batter into the prepared pan and bake for 40-45 minutes, or until a toothpick inserted into the center comes out clean.
Step 8: While the cake bakes, combine sauce ingredients in a saucepan over medium heat. Simmer for 5 minutes until thickened.
Step 9: Poke holes in the warm cake and pour half the sauce over it. Serve the remaining sauce on the side.