Step 1: Soaking the Fruit. Place the mixed dried fruits, cherries, and candied peel in a large bowl. Pour the brandy or orange juice over them. Cover and let them soak for at least 12 hours, or overnight, to plump up the fruit.
Step 2: Preparing the Oven and Pan. Preheat your oven to 300°F (150°C). Grease an 8-inch deep round cake tin and line the bottom and sides with a double layer of parchment paper. This prevents the edges from burning during the long bake.
Step 3: Creaming the Butter and Sugar. In a large mixing bowl, beat the softened butter and dark brown sugar together until the mixture is light, fluffy, and well-combined. This should take about 3 to 5 minutes.
Step 4: Incorporating the Eggs. Add the eggs one at a time, beating well after each addition. If the mixture starts to curdle, add a tablespoon of the flour to help stabilize it.
Step 5: Adding Dry Ingredients and Spices. Sift the flour, cinnamon, nutmeg, and cloves into the bowl. Fold the dry ingredients into the butter mixture gently using a large spoon. Stir in the treacle, orange zest, and lemon zest.
Step 6: Folding in Fruits and Nuts. Gently fold the soaked fruit (including any liquid left in the bowl) and the chopped nuts into the batter. Ensure everything is evenly distributed without overworking the batter.
Step 7: Baking the Cake. Spoon the mixture into the prepared tin and smooth the top with the back of a spoon. Bake in the center of the oven for 3 to 3.5 hours. The cake is done when a skewer inserted into the center comes out clean.
Step 8: Cooling and Feeding. Let the cake cool in the tin for 15 minutes before transferring it to a wire rack. Once completely cold, you can “feed” the cake by poking small holes in the top and drizzling over 1-2 tablespoons of brandy.