**Prepare cheesecake filling:** In a medium bowl, gently combine soft cheese, salted caramel sauce, and icing sugar using a spatula until just combined. Avoid overmixing. Portion into 16 equal portions on a lined baking tray and freeze for at least 2 hours until completely solid.

**Make cookie dough:** In a stand mixer bowl with paddle attachment, cream cold butter and brown sugar on medium speed for 3-4 minutes until light and fluffy. Add egg and vanilla extract, mixing until incorporated.

**Add dry ingredients:** In a separate bowl, whisk together flour, cornflour, bicarbonate of soda, and sea salt. Gradually add to butter mixture on low speed until just combined. Fold in chopped chocolates with a wooden spoon.

**Assemble cookies:** Preheat oven to 180°C (160°C fan). Line two baking trays with parchment paper. Divide dough into 16 portions. Flatten each in your palm, place frozen filling in center, wrap dough around filling, and seal edges completely. Roll gently into smooth balls.

**Bake:** Place cookies 5cm apart on prepared trays. Bake 11-12 minutes until edges are lightly golden and centers still look slightly soft. Cool on trays for 10 minutes before transferring to wire rack.

**Chill and serve:** Chill cookies completely before serving for best texture. The cheesecake filling will set properly when cold.