Preheat oven to 350 degrees.
In a large bowl, add the dry cake mix, oil, and eggs. Stir with a spoon until all ingredients are combined or use a mixer and mix for about 1 minute. It is a sticky and thick batter, so a mixer is easier.
Add the M&M’s, white chocolate chips, and nonpareils, mix with a spoon.
Using a 1.5-inch cookie scoop, scoop dough and place on a parchment lined cookie sheet about 2 inches apart.
Press additional M&M’s and chocolate chips into the cookie ball if you’d like.
Bake for 8-9 minutes or just until the edges are slightly golden brown.
Take them out and let your cookies cool.