In a medium bowl, mix together graham cracker crumbs, granulated sugar, and melted butter until well combined.
Press the mixture firmly into the bottom of an 8x8 baking dish, making sure it’s evenly spread. Let it chill in the freezer for about 10-15 minutes to firm up.
In a large mixing bowl, beat the cream cheese and pudding mix together until light and fluffy. Mix in undrained crushed pineapple. Stir until the mixture begins to thicken.
Gently fold in half of the whipped topping, along with the mini marshmallows, and coconut (if using).
Spread the pistachio mixture evenly over the cooled graham cracker crust.
Spread the remaining whipped topping evenly over the top of the pistachio layer, creating a smooth, creamy topping.
Cover with plastic wrap and refrigerate for at least 4 hours, or preferably overnight, to allow the flavors to meld.
Before serving, garnish with maraschino cherries and a sprinkle of extra pistachio for a beautiful finish. Slice and serve chilled. Enjoy!