Chop the white chocolate and dark chocolate into rough chunks and set aside.

Using a freestanding mixer or a handheld electric whisk, beat together the room-temperature butter, light brown soft sugar and golden caster sugar together for 2 minutes, until light and fluffy.

Beat in the egg and vanilla extract. Add in the plain flour, bicarbonate of soda, baking powder and sea salt. Beat on a low speed until just combined.

Stir the chocolate chunks through and bring the dough together using your hands or a wooden spoon. Chill for an hour to firm up.

Preheat the oven to 180°C, Fan 160C, gas 4. Spoon the cookie dough into a non-stick frying pan and roughly flatten using the back of a spoon. Bake for 20 minutes, until pale golden.

Leave to cool for a few minutes (being cautious of the hot frying pan handle) before serving on the centre of the table with scoops of ice cream in the middle.