Preheat your oven to 350°F (175°C) to ensure even baking.
Line a baking sheet with parchment paper to prevent sticking.
In a large mixing bowl, combine the melted unsalted butter, room temperature egg, vanilla extract, and Neufchatel cheese. Blend until smooth and creamy.
Gradually add the funfetti cake mix to the wet ingredients and mix until just combined.
Fold in the colored jimmies gently until evenly distributed.
Using a cookie scoop or tablespoon, portion out the dough onto the prepared baking sheet, leaving space between each cookie.
Bake for 10-12 minutes, or until the edges are lightly golden and the centers look slightly underbaked.
Let the cookies cool on the baking sheet for about 5 minutes before transferring them to a wire rack to cool completely.
