Gradually stir flour mixture in to butter mixture.
Stir in chocolate chips and set aside.
2 cups semisweet chocolate chips
Remove Funfetti mixture from freezer and use a spoon to form 2-3 tsp sized balls. Set on a wax-paper lined plate (should form 24 balls. If the frosting becomes to sticky to manage while you are scooping, return to freezer for 5 minutes before trying again).
Return to freezer.
Scoop cookie dough into 2 ½- 3Tbsp sized balls (I used a ¼ measuring cup and filled about ⅔-¾ of the way), lightly roll into balls and place on cookie sheet (should make 24 balls of cookie dough)
Remove funfetti filling from freezer and, working quickly, press into cookie dough balls and fold cookie dough around the filling, sealing the funfetti inside completely so it is not visible from outside the cookie (some of the filling will show once the cookies are done baking, but there should be NO filling visible when they go in the oven, otherwise the filling may leak everywhere). Place on parchment paper-lined cookie sheet and gently, slightly press down to lightly flatten (if any filling becomes exposed, seal it up). Repeat until all cookies are sealed around funfetti frosting (you may have some filling left over, that's OK, don't try to cram it all in).
Place prepared cookie dough balls in freezer and chill for at least 30 minutes.
Preheat oven to 375.
Once cookies have chilled, place about 2" apart on a cold parchment paper-lined baking sheet.
Bake at 375F 13 minutes. Allow to cool completely on baking sheet (cookies are fragile and will break easily when hot). While each batch bakes, keep the waiting cookie dough balls in the freezer.
Do not put cookie dough on hot baking sheets or the dough may begin to melt before it can bake, yielding messy cookies.