Make the biscuit base: Place 300g of Oreo biscuits (filling and all) into your food processor. Blitz until you have a fine, dark crumb that resembles damp sand. If you haven't got a processor, put the biscuits in a zip-lock bag and bash them with a rolling pin until they are uniformly crushed. You want the texture to be consistent, with no large chunks remaining. The crumbs should feel slightly claggy when you press them between your fingers.

Bind the base: Pour the melted butter over the biscuit crumbs and stir with a fork until every crumb is coated. The mixture should look like wet, dark soil and hold together when you squeeze a handful. Tip the mixture into your springform tin and press it down firmly and evenly using the bottom of a glass or a flat measuring cup. The base should feel solid and compact, not loose and crumbly. Place this in the fridge to firm up while you make the filling.

Whip the cream: In a large, clean bowl, pour in the double cream and sifted icing sugar. Using your electric mixer, whisk on a medium speed until the cream holds soft peaks. You'll know it's ready when you lift the beaters and the cream forms a gentle peak that flops over at the tip. The cream should look glossy and thick, not grainy or stiff. Set this bowl aside.

Make the cream cheese mixture: In a separate large bowl, beat the softened cream cheese with the caster sugar and vanilla extract. Beat on a medium speed until the mixture is completely smooth, silky, and lump-free. Scrape down the sides of the bowl at least once. The texture should be like a thick, luscious mousse, with no gritty sugar remaining. I used to struggle with this step until I discovered the importance of truly softened cream cheese; cold cheese will leave you with lumps.

Fold everything together: Take a large spoonful of the whipped cream and fold it into the cream cheese mixture to loosen it. This is called 'lightening the mix'. Then, gently fold the remaining whipped cream into the cream cheese until just combined. The mixture should be pale, airy, and voluminous. Finally, fold in the roughly chopped Oreo pieces. You want them evenly distributed throughout the pale filling, creating a lovely speckled effect. I stumbled upon this combination by accident, and it's been a hit ever since.

Assemble and chill: Spoon the filling onto the chilled biscuit base. Use a spatula to spread it evenly, right to the edges. Gently tap the tin on the worktop a couple of times to release any air bubbles. The surface should be smooth and flat. Cover the tin with cling film or foil and place it in the refrigerator for a minimum of 4 hours, though overnight is far better. The cheesecake should feel firm to the touch and set cleanly when sliced.

Serve and decorate: Once set, run a warm, dry knife around the edge of the tin before releasing the springform clasp. Slice the cheesecake with a sharp knife, wiping the blade clean between each cut for neat, clean slices. Decorate with extra whole or halved Oreos and a light dusting of icing sugar just before serving.