Preheat your oven to 350°F. Line a baking sheet with parchment paper.

In a medium bowl, whisk together the flour, baking soda, and salt. Set aside.

In a large bowl, cream together the softened butter, granulated sugar, and brown sugar until light and fluffy. Add the vanilla extract and egg, mixing until well combined.

Gradually add the dry ingredients to the wet mixture, stirring until just combined. Fold in the red and blue sprinkles.

Using a tablespoon, drop rounded balls of dough onto the prepared baking sheet, spacing them about 2 inches apart. Bake for 10-12 minutes or until the edges are lightly golden. Allow cookies to cool on the baking sheet for 5 minutes before transferring to a wire rack to cool completely.

Once the cookies are cool, take one cookie and scoop a generous amount of vanilla ice cream onto the flat side. Top with another cookie, flat side down, and gently press together. Repeat with remaining cookies and ice cream.

Place the assembled ice cream sandwiches in the freezer for at least 30 minutes to firm up before serving.