Preheat your oven to 180C/160C Fan and line a 9x9" square tin with parchment paper.
In a large bowl, add your melted butter and sugars and beat until smooth.
Add in the eggs and beat again until smooth.
Add in the flour and cornflour and beat until a thick blondie mixture is made - it really doesn't take long to create this mixture!
Add in your white chocolate and fold through!
Pour the mixture into the tin, and spread. Dollop on the caramel, and lightly swirly through the blondie mixture.
Bake the blondies in the oven for 30 minutes, or until there is an ever so slight wobble in the middle. (See notes below)
Leave to cool in the tin. Drizzle over some extra caramel if you fancy!
Notes
I've updated the butter quanitity to be 200g rather than 250g as it was occasionally being greasy for readers - if you liked it at the 250g quantitiy you can still use it!
The bake time can vary - please make sure your oven is on the correct setting, and check from 25+minutes and onwards till they are baked! These took 30 minutes in my fan oven.
If they turn out cakey, they are over baked - that's all! Bake for a little less time next time.
One good tip if you aren't sure is to bake them till they have the wobble, and then once cooled, put them in the fridge for at least an hour to help 'set' them before cutting up!
These will last in a cake tin for 4-5 days+
I keep them at room temperature.
I used Carnations caramel for the caramel - but do NOT add more than 150g to the mix unless you are 100% sure you've got the blondie mix right. If you add too much, it probably won't bake very well at all.
The drizzle of caramel on top is completely optional!