Preheat oven to 350°F and line a 8x8 or 9x9 square pan with parchment paper; set aside
With stand mixer and paddle attachment cream together butter, oil and both sugars for 5 mins.
Scrape down the bowl and add eggs and vanilla and mix another minute.
Add baking soda, salt and flour and mix on low until just combined.
Add sprinkles and white chocolate chips and mix for just about 10 seconds, you don't want to overmix batter.
Spread batter evenly onto prepared pan and top with a few more chocolate chips if you like then bake for 25-30 mins.
Remove from oven and let cool for 10 mins. before removing from pan to completely cool.