Preheat oven to 350℉.

Place ½ cup of the chocolate chips on a cutting board and use a large knife to chop into small pieces (set the other ½ cup of unchopped chocolate chips aside).

In a small microwave-safe bowl, melt the ½ cup unsalted butter for 20-30 seconds until JUST melted.

Transfer butter to a larger mixing bowl and add ¼ cup granulated sugar and ½ cup light brown sugar and use a spatula to stir until combined.

Add in 1 large egg and 1 ½ teaspoon vanilla extract, then mix.

Next, add in ½ teaspoon baking soda, ¼ teaspoon baking powder, and ¼ teaspoon salt and mix again.

Add in 1 ½ cups all-purpose flour and mix until all the flour disappears into the dough.

Add the ½ cup of chopped chocolate chips and ½ cup of whole chocolate chips into the dough and mix.

Grease a 11.5" metal cookie cake pan.

Using a spoon or your clean hands, drop the dough into small chunks in the pan.

Once all dough has been added, use a spatula or your hands to press down the dough into a smooth layer.

Bake at 350℉ degrees for 12-14 minutes.

Remove from oven and place entire pan on a cooling rack. Allow the cookie cake to cool completely before removing.

To remove from pan, use a knife to go around the edges, place a flat platter on top, then flip over the pan to remove.

Using a large star piping tip, pipe around the edges then immediately add sprinkles.

To make frosting, beat the softened ¼ cup unsalted butter on medium-high speed for 2-minutes until smooth.

Turn the mixer to low speed then add the powdered sugar ¼ cup at a time.

Add ¾ teaspoon vanilla extract and a pinch of salt and turn mixer to medium speed.

One tablespoon at a time, add 1-2 tablespoons milk. Beat on high for 2-3 minutes until creamy.