Using an electric mixer, beat butter until it is fluffy
Add in both brown and white sugar and cream them with the butter.
In a separate bowl, sift together flour, baking soda, corn starch and salt.
Add the dry ingredients to the butter mixture and mix until blended.
Add pistachios and white chocolate chips. Using a spatula or a whisk, carefully mix them into the batter
Scoop out your dough into balls of equal sizes on a baking tray lined with baking sheet. Refregerate for 30 minutes
Pre heat your oven to 170C.
Bake for about 12-15 minutes or until the edges become golden brown.
After taking them out of the oven, let them rest on the baking tray for at least 10 minutes..