Preheat the oven to 350°F (150°C) Line a baking sheet with parchment paper to get it ready for use.
Roll out the chocolate chip cookie dough into 1 ½ inch round balls. Roll in the funfetti sprinkles and place on the baking sheet. Flatten slightly with finger tips. Repeat with the cookie dough to make 12 cookies.
Place in the oven and bake for 12-14 minutes or until the edges are just lightly browned.
While the sugar cookies are baking, make the cream cheese frosting filling.
Combine the cream cheese, powdered sugar, and vanilla extract in a mixing bowl.Use a hand mixer to blend everything together until completely combined.
Then add the milk and mix again until the cream cheese is a smooth texture. If it is still a bit thick add another teaspoon or tablespoon of milk.
Place the frosting in a piping bag.
Once the cookies are done, let them cool completely on the baking sheet or transferred to a wire rack.
After the cookies are cooled, flip over 6 of the cookies, so that the bottom is facing up.
Cut a hole in the cream cheese frosting filled piping bag and pipe a thick swirl of frosting on each of the 6 cookies.
Place the other 6 cookies on top of the frosting and squeeze slightly to create cookie sandwiches with the frosting slightly protruding from the edges.
Dip the edges of the cookies into the funfetti sprinkles if desired for an extra pop of colors. Enjoy