Cream together the butter and the salt, might take a while but it's worth it!
Add in the egg yolk! Just the yolk though, make the white into an omelette or something yummy :) here add in the vanilla if you have some
Add both sugars to make it sweet~~
And finally mix in the flour to make it... Like a cookie! The recipe says to use plain/all-purpose flour but self-raising worked when I used it :)
Finally mix in half of your chocolate and put the other half on top! <3 ah looks good
Waah~ microwave it for a minute on high. Mine's 1000w so adjust time accordingly to how crispy you want it~
Feel free to adapt this to however you want! Use dried fruit, add cocoa powder, get wacky with it!