Cream the softened butter and sugars until light and fluffy, scraping down the bowl a few times.
Add in half of the beaten egg (about 41g) and a few drops or 1/4 teaspoon of vanilla extract.
In a separate bowl, combine all the dry ingredients: plain flour, bicarbonate of soda, funfetti sprinkles, mini white chocolate chips, and white chocolate chips.
Slowly add the dry mix to the butter mixture and mix until just combined.
Now, you have the dough ready for your cookies. To make 30 cookies:
Divide the dough into 30 equal portions.
Roll each portion into a ball.
Enjoy your batch of 30 Funfetti cookies! You can also prepare the buttercream for cookie sandwiches using the instructions mentioned in the original recipe.