In a mixing bowl add sugar cookie mix, butter and egg. Mix well with a spatula until all combined (note: this can take some elbow grease, so you can use a hand mixer for the start on low to prevent overmixing).

Using a 1 tablespoon cookie scoop, drop dough balls into to fill the muffin tray (you will have enough for 36 cookies).

Bake for about 10-12 minutes, or until you see the tops starting to get a little golden brown.

Remove from the oven and using a tart tamper or a tablespoon lightly press into each cookie to make a small cavity (only go about half the way down, or less).

Allow them to cool for at least 15 minutes to ensure the frosting does not melt.

Once fully cooled remove cookie cups carefully, you may want to use a small spoon to loosen the edges (I like to use my tart tamper and turn it to loosen the cookie then tip the tray over to slide it out).

Then start your cream cheese frosting by adding all ingredients but Cool Whip into the bowl of a stand mixer and mix on medium-low speed until smooth; stopping to scrape the edges down to ensure everyone is smooth and consistent. Fold in Cool Whip.

Transfer to a piping bag and fill each cookie cup. Add sprinkles.