Prepare the White Layer: In a blender, combine 1/3 of your base ingredients (ice, cream of coconut, pineapple juice, and rum if using). Blend until smooth.
Pour into a small pitcher and set aside.
Make the Blue Layer: Clean the blender. Add another 1/3 of your base ingredients plus blue curaçao or food coloring.
Blend until smooth, then pour into a separate pitcher.
Create the Red Layer: Clean the blender again. Add the final 1/3 of base ingredients plus strawberries and grenadine.
Blend until smooth and transfer to a third pitcher.
Assemble the Drink: Start by pouring the red layer into glasses, filling about 1/3 of each glass.
Place in freezer for 5 minutes to set slightly.
Add White Layer: Using the back of a spoon, slowly pour the white mixture over the red layer.
The spoon helps prevent the layers from mixing. Return to freezer for another 5 minutes.
Finish with Blue Layer: Carefully add the blue layer using the spoon technique again.
Garnish: Top with whipped cream, a cherry, pineapple wedge, and a small flag if you’re feeling extra festive.