Preheat your oven to 350°F (175°C) and line a baking sheet with parchment paper.

In a large bowl, cream together the softened butter, granulated sugar, and brown sugar until light and fluffy.

Beat in the eggs one at a time, followed by the vanilla extract, ensuring everything is well combined.

In another bowl, whisk together the all-purpose flour, baking soda, and salt until blended.

Gradually add the dry mixture to the wet ingredients, stirring until just combined to avoid overmixing.

Fold in the rainbow sprinkles, ensuring they are evenly distributed throughout the dough.

Use a cookie scoop or tablespoon to drop rounded balls of dough onto the prepared baking sheet, spacing them about 2 inches apart. Sprinkle a few extra on top for color.

Bake the cookies for about 10-12 minutes, or until the edges are lightly golden. They may look underdone in the center, but will firm up as they cool.

Allow the cookies to rest on the baking sheet for a few minutes before transferring them to a wire rack to cool completely.