Combine together the butter and both sugars in a bowl.

Add the egg and vanilla extract once combined.

In a separate bowl mix together the flour, bicarbonate of soda and chocolate chunks/chocolate chips.

Combine the wet and dry ingredients in a bowl and mix together until just combined.

Once the dough is mixed roll it out into a circular shape, wrap in clingfilm and then chill for a minimum of 1 hour. You can leave it overnight if you'd prefer. Chilling like this helps for a chewier more delicious cookie.

Add the dry ingredients to the wet ingredients and mix until combined well.

If you’re in a hurry you could skip the chilling, but I really feel it adds to the overall texture of the cookies so try to make time for this step!

Take your chilled cookie dough, roll it out and then shape it to fit either a cake pan or a cast iron skillet. Personally I love to use a well seasoned cast iron skillet, as I feel this gives a great result with a chewy cookie with a well cooked bottom.

Pre-heat your air fryer to 180C (350F) for 1-2 minutes if you'd like. I like to do this so the air fryer is ready to go right away.

Remove from the air fryer and then transfer to a wire cooling rack to cool down.

If you used parchment paper then gently peel this back once it's cooled lightly and it'll keep for 2-3 days.