Preheat your oven to 350 degrees Fahrenheit.

Line a springform pan with parchment paper, set aside.

In a large mixing bowl, beat 1/2 cup butter until smooth.

Add the sugars, and cream together for 1-2 minutes.

Add the eggs and 1 1/2 tsp. vanilla, and mix again until just combined.

In a separate bowl, whisk together the all purpose flour, salt, and baking soda.

Slowly mix the dry ingredients until just combined.

Add the chocolate chips and M&Ms, and fold into the dough.

Bake for 20-25 minutes, until the top is beginning to turn golden brown.

After baking, allow the cookie to cool completely.

In another large bowl, beat the remaining 1/2 cup butter, until smooth.

Slowly add the powdered sugar, vanilla extract, and milk.

Mix until well combined.

Add the green gel food coloring and mix until the color is evenly distributed.

Use a closed star tip to pipe the frosting around the outside edge of the cookie cake.

Sprinkle with Christmas sprinkles.