Chocolate Mirror Glaze Cake

Step 1: Refrigerate the cake layers for at least 1 hour, until well chilled for easier handling. Trim the cake to level it, then frost it with chocolate ganache until smooth and level.

Step 2: Once the ganache is smooth and level, refrigerate the cake for at least 1 hour before coating it with mirror glaze.

Step 3: Place the water in a small bowl. Sprinkle the gelatine over the surface and mix just until all the powder is wet. Leave for 5 minutes, until it has a rubbery consistency.

Step 4: Put the cocoa and water in a medium saucepan and mix until almost lump-free. The mixture will form a paste.

Step 5: Add a splash of cream to the cocoa mixture and stir to loosen it. Add the remaining cream and sugar, then mix gently to combine. Do not mix vigorously or use a whisk.

Step 6: Set the stove to medium-high heat. As soon as the mixture comes to a boil, remove it from the heat.

Step 7: Add the gelatine lump and stir gently until it dissolves and the glaze is smooth and glossy. A little white foam is fine.

Step 8: Set a small fine-mesh strainer over a shallow bowl and strain the glaze into the bowl. Keep the strainer close to the bowl as you pour so the glaze falls the shortest distance possible; pouring from a height creates bubbles.

Step 9: Twist the bowl rapidly back and forth between your hands to bring any bubbles to the centre.

Step 10: Cover the glaze with cling wrap, pressing it directly onto the surface to prevent a skin from forming. Leave it on the counter for 2 hours, until it reaches 30°C/86°F.

Step 11: Just before pouring the glaze over the cake, strain it into a jug. Tilt the jug and strainer as you pour to keep the distance the glaze falls as short as possible.

Step 12: Remove the cake from the fridge and transfer it to a rack. Set the rack on a tray to catch excess glaze.

Step 13: Starting in the centre of the cake, pour the glaze in an expanding spiral towards the outer edge, letting it spread across the top and drape down the sides. For the smoothest surface, try to pour in one continuous motion. Pour in a confident, steady stream rather than a thin drizzle, which can set too quickly and leave drips.

Step 14: Check that all sides are coated. If any patches are bare, quickly pour a little glaze down those sides.

Step 15: Before the glaze sets, in about 10 minutes, move the cake to a cake platter.

Step 16: Use excess glaze from the tray or jug to fill gaps and tears. Smooth the patches with a warmed palette knife, warmed lightly with a blow torch or dipped in warm water and wiped dry.

Step 17: Fill a tall jug with warm tap water. Dip a knife into the water, wipe it dry, and make one cut into the cake.

Step 18: Clean the knife, dip it in warm water and dry it again. Make a second cut to form a wedge, then remove the wedge. Continue cutting slices, cleaning and warming the knife between cuts.