Make the yellow lemon layer first: In a pot, mix ¾ of the sugar with the cornstarch and salt. Slowly pour in the water while stirring until it's smooth.

Turn on the heat to medium and bring it to a boil, stirring the whole time. Once it's boiling, turn down the heat a bit and add the rest of the sugar and the lemon juice. Keep cooking and stirring for about 2 minutes until it gets thick like pudding.

Take it off the heat and mix in the butter, lemon zest, and food coloring if you're using it. Let this cool down to room temperature (about 1 hour).

Now make the cream cheese layer: In a bowl, beat the softened cream cheese and powdered sugar together until it's smooth and creamy.

Gently fold in the Cool Whip and 1 tablespoon lemon juice until it's all mixed together.

Save some for later: Take out about ½ cup of this cream cheese mixture and put it in the fridge for later (we'll use it to decorate!).

Put it all together: Spread the cream cheese mixture into the bottom of your pie crust.

Pour the cooled lemon filling on top and spread it out evenly.

Cover it loosely with plastic wrap and put it in the fridge overnight.

When you're ready to eat it: Cut the pie into slices and put a little swirl of the saved cream cheese mixture on top of each slice.