Chop your 1 cup of froot loops using a knife, kitchen mallet, or in a food processor. Leave them a little chunky so there are pieces in the finished cookies. Set aside.
Pulverize your 1/3 cup froot loops in a food processor. Set aside.
In a separate bowl, whisk flour, cornstarch, salt, and baking soda until combined. Set aside.
Beat butter and sugar in a stand mixer or using a hand mixer for 2-3 minutes.
Add egg and mix for 1 minute. Scrape down sides of bowl, as needed.
Add vanilla and mix until combined.
Gently add dry ingredients and mix until just combined.
Then, fold in the chopped froot loops and white chocolate chips until combined.
Scoop dough balls using a cookie scoop and then roll in the pulverized froot loops and place on a parchment or silicone lined baking sheet. It should make about 12 - 15 cookies.
Place baking sheets in refrigerator for at least an hour or overnight.
Preheat oven to 350 degrees F when ready to bake.
Bake for 9-11 minutes until edges are just barely brown.
