Step 1: In a large bowl, combine the mixed dried fruit with the brandy, rum, or orange juice. Cover and let soak overnight, or for at least 8 hours, stirring occasionally.
Step 2: Preheat your oven to 300°F (150°C). Grease and line an 8-inch round cake pan with parchment paper, ensuring the paper extends above the rim by about 2 inches.
Step 3: In a medium bowl, whisk together the flour, baking powder, salt, cinnamon, nutmeg, and cloves. Set aside.
Step 4: In a separate large bowl, cream together the softened butter and dark brown sugar until light and fluffy. Beat in the eggs one at a time, mixing well after each addition. Stir in the black treacle or molasses.
Step 5: Gradually add the dry ingredient mixture to the wet ingredients, mixing on low speed until just combined. Do not overmix.
Step 6: Fold in the soaked fruits (including any remaining liquid) and the chopped nuts until evenly distributed throughout the batter.
Step 7: Pour the batter into the prepared cake pan and smooth the top. Place the cake pan on a baking sheet.
Step 8: Bake for 2 hours and 30 minutes, or until a wooden skewer inserted into the center comes out clean. If the top starts to brown too quickly, you can cover it loosely with aluminum foil.
Step 9: Remove the cake from the oven and let it cool in the pan for 15-20 minutes before inverting it onto a wire rack to cool completely.
Step 10: Once cooled, if desired, 'feed' the cake by brushing a tablespoon of brandy or rum over the top. Wrap the cake tightly in parchment paper and then aluminum foil, and store in an airtight container in a cool, dark place. Repeat 'feeding' weekly for up to a month to deepen flavor and moisture.