Preheat and prepare the tin: Set your oven to 160°C (140°C fan). Line the base of a 20cm springform tin with a circle of baking parchment and lightly grease the sides. The smell of warm butter and chocolate will start filling your kitchen right about now.

Make the base: Blitz 200g of the Oreos (about 17 biscuits) in a sealed plastic bag using a rolling pin, or pulse them in a food processor until you have fine, dark crumbs with no large chunks. Pour the crumbs into a bowl, add the melted butter, and stir until every crumb looks damp and smells rich and buttery. Press this mixture firmly into the base of your prepared tin using the back of a spoon. You'll feel it compacting into a solid, even layer. Bake for 10 minutes, then set aside to cool. The base will look slightly darker and smell deeply of chocolate.

Start the filling: In a large mixing bowl, beat the cream cheese with an electric mixer on medium speed until it looks smooth and glossy, with no lumps visible – about 2 minutes. You'll see it soften and become pale and creamy. Add the caster sugar and vanilla extract, and beat for another minute until the mixture looks light and airy, almost like thick frosting.

Add the eggs one at a time: Crack in the first egg and beat on low speed until just combined – you'll see the yellow ribbon disappear into the white mixture. Repeat with the second and third eggs, scraping down the sides of the bowl after each addition. The batter should look smooth, silky, and uniform in colour.

Finish the filling: Pour in the double cream and add the flour and salt. Beat on low speed until everything is incorporated – about 30 seconds. The batter will look thick, glossy, and pourable, with a slight sheen on top. Fold in the 100g of crushed Oreo pieces using a spatula. You'll see dark swirls and chunks throughout the pale filling.

Assemble and bake: Pour the filling over the cooled base and spread it evenly with a spatula. Tap the tin gently on the counter twice to release any air bubbles – you'll hear a soft thud. Bake for 50–55 minutes. After 45 minutes, check for doneness: the edges should look set and slightly puffed, while the centre should wobble gently when you shake the tin, like a firm jelly. The kitchen will smell incredible – warm cream cheese and chocolate.

Cool slowly: Turn off the oven, crack the door open with a wooden spoon, and let the cheesecake cool inside for 1 hour. This gentle cooling prevents cracking. After an hour, transfer to a wire rack to cool completely. You'll see the surface settle and become smooth and flat. Once cool, refrigerate for at least 4 hours, ideally overnight. The texture firms up beautifully – it should feel dense but silky when you cut into it.