Instructions

• In a large bowl, beat the room-temperature butter, light brown sugar, and granulated sugar until smooth, light, and creamy. Scrape down the sides of the bowl as needed.
• Add the egg and vanilla extract and mix until just combined.
• In a separate bowl, whisk together the baking soda, salt, unprepared instant vanilla pudding mix (dry), unprepared Funfetti or yellow cake mix (dry), and the flour until evenly combined.
• Add the dry ingredients to the wet ingredients and mix on low speed (or stir with a sturdy spoon) until just combined. Do not overmix—the dough will be very thick.
• Gently fold the sprinkles and white chocolate chips into the dough with a spatula until evenly distributed.
• Form the dough into round balls, each 3 tablespoons (about 60 grams).
• Place the dough balls on a tray, cover, and chill in the refrigerator for at least 1 hour.
• When ready to bake, preheat the oven to 350°F. Line a baking sheet with parchment paper or a silicone baking mat.
• Place no more than 6 chilled dough balls on each prepared baking sheet, leaving space for the cookies to spread.
• Bake for 9–13 minutes, or until the edges are lightly browned and the centers are still slightly underbaked (about 11 minutes is typical).
• Remove the baking sheet from the oven and let the cookies cool on the sheet for 3–4 minutes. If desired, press a few extra white chocolate chips and sprinkles onto the tops while the cookies are warm.
• Transfer the cookies to a wire rack to cool completely. Cookies are best enjoyed the same day they’re made.