In a 10" oven-proof pan, melt the butter over low heat.
Once completely melted, remove from heat, then add the sugars and vanilla, mixing until completely incorporated.
When they pan is cool enough to touch for a few seconds, add the egg and stir thoroughly.
Add the flour, baking soda and white chocolate chips and continue mixing until all the ingredients are full incorporated, then gently spread to cover the bottom of the pan.
Place pan in a 350 degree oven and bake for 20-25 minutes, or until the top is golden brown.