180gunsalted butter6.4 oz/ 3/4 cup, room temperature
180 gmuscovado sugar6.5 oz/ 1 cup
2eggs
100mlmilk3.4 fl.oz/ scant ½ cup
5tablespoonsrum
Mirror glaze:
4gelatine sheets10 g/ 0.35 oz
125mlcold water4.2 fl.oz/ ½ cup
225ggranulated sugar8 oz/ 1 cup + 2 tablespoons
150gcouverture chocolate5.3 oz
30gunsweetened cocoa powder1 oz/ ½ cup
65mlheavy cream35% fat,2.3 fl.oz/ ¼ cup + 1 tablespoon
Instructions
Cake:
Preheat the convection oven to 180 degrees Celsius/ 350 degrees Fahrenheit. Butter the bottom of a 20 cm/8-inch springform and line it with baking paper.
Finely grate the dark chocolate and the zucchini.
Mix the flour, cocoa powder, baking powder, and salt and set aside.
Combine: Cream the butter and the muscovado sugar for about 5 minutes. Add the eggs, one at a time, mixing well in between. Add the flour mixture, the milk, and the rum by turns, in 2 or 3 batches. Finally, fold in the chocolate and zucchini.
Bake: Pour the mixture into the prepared springform and bake for about 1 hour. Check if the cake is done by inserting a toothpick in the middle. Leave the cake to get cold, then chill it. It has to be well chilled before glazing.
Mirror glaze:
Soak the gelatine leaves in cold water for about 10 minutes or according to the packet's instructions.
Dissolve gelatine: Pour the water into a small saucepan. Let it come to a boil and add the sugar. Stir well, remove from heat and add the chopped couverture chocolate. Mix with a hand whisk, add the sifted cocoa powder, mix well and add the heavy cream. Mix again, and when the temperature reaches 60 degrees Celsius/ 140 degrees Fahrenheit, stir in the squeezed gelatin leaves and mix until dissolved.
Sieve this mixture into a jug and blend with a hand blender. Sieve again into another jug and let cool until the mixture reaches 29 degrees Celsius/ 84 degrees Fahrenheit.
Glaze: Place a small casserole form that is slightly smaller than the cake in a large roasting tin. Place the chilled cake on top of the small form and start pouring the glaze over it. Remove excess glaze from under the cake with a knife. Refrigerate the cake until serving or decorating.
Notes
Always use a digital kitchen scale in baking; it ensures the best results (Amazon affiliate link).