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.

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

Add the vanilla extract and egg to the butter mixture, mixing until well combined.

Gradually add the dry ingredients to the wet ingredients, 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 8-10 minutes or until the edges are lightly golden. Remove from the oven and let 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, add a scoop of vanilla ice cream, and top with another cookie to create a sandwich. Repeat with the remaining cookies and ice cream.

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