Preheat the oven at 160ºC/325ºF, conventional oven.

In a food processor, blend the cookies, cocoa powder and granulated sugar until a fine sand-like texture. Melt the butter. Add the melted butter to the food processor and blend it together with the blended cookies.

In a 22 cm spring cake pan add parchment paper to the bottom. Add the cookie crumbs and press the cookie crust down with the bottom of a glass, and up against the side of the pan, so it’s well packed together and flattened out. Bake it for 10 minutes. Then let it cool down so that it’s cool to touch.

Keep the oven temperature at 160ºC/325ºF conventional oven.

Melt the milk chocolate and heavy cream together in the microwave or over a double boiler, and set it aside.

Add the orange zest into a bowl with granulated sugar. Rub together the granulated sugar and orange zest. It will almost look like wet sand.

With a hand mixer or in a stand mix using the paddle attachment, cream the cream cheese for 1 minute on low speed. Then gradually add the granulated sugar. Once all the granulated sugar is added, scrape down the sides of the bowl and let it mix for 1 minute on low speed.

In a small bowl, mix together the sour cream and cornstarch until smooth. Add it to the cream cheese with the orange marmalade and vanilla extract and let it mix on low speed until combined. Then add one egg at a time and let it mix on low speed until combined. Once all the eggs have mixed in, add the melted milk chocolate and mix it in. Scrape down the sides of the bowl and give it a final mix to make sure all the ingredients have incorporated.

Pour the cheesecake batter into the spring pan.

Boil up water in a kettle. Place the springform pan in a 25 cm/10 inch cake pan. Place the cake pan in another baking pan or roasting pan and fill it with hot water ⅔ up the side of the pan. This method will prevent water from getting into the crust.

Alternatively, add a triple layer of aluminium foil around the cake pan to safely seal it from the water before placing it in a water bath. There might be a possibility of water leaking in, so make sure it's covered well if choosing this method.

Bake for 1 hour and 20 minutes.

Once the time has passed, give the tray a very gentle shake. The cheesecake should still be a bit wobbly in the middle. Turn off the oven and have the oven door slightly open and let the cheesecake cool down in the oven for 1 hour.

Then take it out of the oven and remove it from the water bath. If added, take off the aluminium foil and place the cheesecake on a cooling rack. Let it cool down fully for about 1 hour to room temperature. Finally, once at room temperature, place it in the fridge and let it set for at least 6 hours, preferable overnight.

Start by slicing the orange peel into thin slices.

Add the water and granulated sugar to a wide saucepan. Stir it together and bring a simmer. Then add the orange slices and let them simmer for 30-40 minutes. The white part of the orange peel should be fairly translucent. Swirl the pan once in a while to make sure the slices are covered with the syrup.

Gentle lift the slices out of the saucepan and onto a wire rack to dry for 2 hours or overnight.

Melt the milk chocolate, heavy cream and orange juice together in the microwave or over a double boiler. Take it off the heat and stir it together until smooth.

Pour it over the cheesecake and even it out. Decorate with the candied oranges and orange zest. Keep it stored in the fridge.