Preheat the oven to 180C (300F). Line a baking tray with baking paper, then line a cake tin with baking paper on the bottom and grease the edges with butter.

In a food processor combine the Oreos, digestives and melted butter until a fine crumb has formed (If you don't have a food processor I used a rolling pin with a zip lock bag to bash the biscuits before mixing with the butter). Press into the bottom of the cake tin ensuring that it completely covers the base evenly. Place the cake tine in the fridge to cool the base. 

Using a stand mixer, combine the cream cheese and sugar until smooth. Add the Baileys, beating until combine, and then add the eggs one by one, allowing each to mix through fully before adding the next. Add the sour cream and vanilla, then once that is mixed through add the flour and beat until just combined. Stir through half of the chocolate chips. 

Remove the cake tin from the fridge and place on the baking tray. Pour the cake batter into the cake tin, and fold in the remaining chocolate chips to the top of the cheesecake (don't worry too much about it being too full as it won't rise too much).

Bake for 1 hour on the baking tray, then turn off the oven and leave the door closed. Allow the cheesecake to sit for 3-5 hours to cook fully through, and then remove from the oven and refrigerate to cool completely. 

When you are ready to serve the cake, remove from the tin and place on a serving plate. Using the whisk attachment of your stand mixer, beat the heavy cream, icing sugar and vanilla extract until light and fluffy, about 5 minutes. 

To decorate the cake, use a spatula to generously dollop the cream around the edge of the cake. You can use a piping tool for this but that's up to you, I personally liked the dolloped look. Once you've placed all the cream around the edges, push in the snickers pieces to the cream intermittently, and then garnish by drizzling salted caramel sauce over the cream and snickers. Place in the fridge until you are ready to serve.