Directions
<ol class="no-list-style"><li class="MethodStepper"><h4 class="step-title">Step 1</h4>Preheat your oven to 160°C (325°F) and position the rack in the middle. Wrap the outside of a 23cm springform pan with two layers of heavy-duty aluminum foil, ensuring it comes at least 5cm up the sides. This prevents water from seeping into your cheesecake during the water bath baking.</li><li class="MethodStepper"><h4 class="step-title">Step 2</h4>For the crust, pulse the chocolate biscuits in a food processor until finely ground. Add the melted butter and sugar, pulsing until the mixture resembles wet sand. Press the mixture firmly and evenly into the bottom of your prepared springform pan. Use the bottom of a measuring cup to compact it firmly - this helps prevent a crumbly crust. Bake for 10 minutes, then remove and cool completely on a wire rack.</li><li class="MethodStepper"><h4 class="step-title">Step 3</h4>For the filling, melt the dark chocolate either in a heatproof bowl over simmering water (ensuring the bowl doesn't touch the water) or in 30-second bursts in the microwave, stirring between each burst. Once smooth, set aside to cool slightly but remain fluid.</li><li class="MethodStepper"><h4 class="step-title">Step 4</h4>In a stand mixer fitted with the paddle attachment, beat the cream cheese on medium speed until completely smooth and free of lumps, about 3 minutes. Scrape down the sides frequently - this detail is crucial for a silky-smooth cheesecake. Add the sugar and beat for another 2 minutes until well incorporated.</li><li class="MethodStepper"><h4 class="step-title">Step 5</h4>Reduce mixer speed to low and add eggs one at a time, mixing just until each is incorporated. Over-mixing after adding eggs can incorporate too much air, leading to cracks during baking. Add the sour cream, heavy cream, and vanilla, mixing just until combined.</li><li class="MethodStepper"><h4 class="step-title">Step 6</h4>Sift in the cocoa powder and salt, mixing on low until just incorporated. Pour in the melted chocolate and fold gently with a spatula until fully combined and the mixture is a uniform chocolate color. The batter should be smooth, glossy, and relatively thick.</li><li class="MethodStepper"><h4 class="step-title">Step 7</h4>Pour the batter into the cooled crust, smoothing the top with a spatula. Place the foil-wrapped springform pan into a large roasting pan. Carefully pour hot water into the roasting pan until it reaches about halfway up the sides of the springform pan. This water bath creates gentle, even heat and adds humidity to prevent cracking.</li><li class="MethodStepper"><h4 class="step-title">Step 8</h4>Bake for 60-70 minutes, or until the edges are set but the center still has a slight wobble when gently shaken - it should jiggle like set jelly, not ripple like liquid. Do not open the oven during baking as temperature fluctuations can cause cracks.</li><li class="MethodStepper"><h4 class="step-title">Step 9</h4>When done, turn off the oven, crack the door open slightly, and let the cheesecake cool in the oven for 1 hour. This gradual cooling prevents the dramatic temperature change that can cause the top to crack. Remove from the water bath, peel off the foil, and let cool completely on a wire rack.</li><li class="MethodStepper"><h4 class="step-title">Step 10</h4>Once completely cool, cover the cheesecake with plastic wrap and refrigerate for at least 6 hours, preferably overnight. This chilling time is essential for the perfect texture - patience will be rewarded!</li><li class="MethodStepper"><h4 class="step-title">Step 11</h4>For the ganache topping, place the chopped chocolate in a heatproof bowl. Warm the heavy cream in a small saucepan until it just begins to simmer at the edges. Pour over the chocolate and let sit for 2 minutes, then stir until smooth. Add the butter and stir until glossy. Let cool for 5-10 minutes until slightly thickened but still pourable.</li><li class="MethodStepper"><h4 class="step-title">Step 12</h4>Remove the chilled cheesecake from the springform pan and place on a serving plate. Pour the ganache over the top, spreading to the edges and allowing some to drip attractively down the sides. Return to the refrigerator to set the ganache for at least 30 minutes before serving. For clean slices, dip your knife in hot water and wipe dry between cuts.</li></ol>