Create the 'Dirt': Place the Oreo biscuits (the entire biscuit, cream filling and all) into a food processor and pulse until they resemble fine crumbs, like soil. If you don't have a food processor, place them in a sturdy zip-top bag and crush them with a rolling pin.

Make the Buttery Base Layer: Scoop out about one cup (around 100g) of the plain Oreo crumbs and set aside for the topping later. Add the melted butter to the remaining crumbs in the food processor (or a bowl) and pulse or stir until the mixture resembles damp sand.

Form the Base: Press this buttery crumb mixture firmly and evenly into the bottom of a 2.5-litre trifle bowl or a 20x20 cm glass baking dish. Place it in the fridge to firm up while you prepare the filling.

Prepare the Cream Cheese Mixture: In a large bowl, using a stand mixer or an electric hand mixer, beat the room-temperature cream cheese until it's completely smooth and free of lumps. Add the sifted icing sugar and vanilla extract and beat again on medium speed for 1-2 minutes until light and fluffy.

Whip the Cream: In a separate, clean bowl, whip the cold double cream until it holds stiff peaks. Be careful not to over-whip it, or it will become grainy. A great guide on achieving the perfect consistency can be found on Serious Eats.

Combine the Fillings: Gently fold the whipped cream into the cream cheese mixture using a spatula. Do this in two or three additions to keep the mixture light and airy. Stop folding as soon as it's combined to avoid deflating the cream.

Assemble the Layers: Remove the base from the fridge. Spread the cream cheese mixture evenly over the Oreo crust.

Add the Final Topping: Sprinkle the reserved plain Oreo crumbs evenly over the cream cheese layer to create the final 'dirt' topping.

Chill Thoroughly: Cover the dish with cling film and refrigerate for at least 4 hours, or preferably overnight. This step is crucial for the flavours to meld and for the filling to set completely.

Decorate and Serve: Just before serving, decorate with gummy worms poking out of the 'dirt' or some fresh raspberries. Serve chilled, directly from the dish.