Prepare your ingredients: cut fresh pineapple if using, and measure out everything.
In a blender, add ice cubes, pineapple chunks, cream of coconut, and Malibu rum.
Blend on low, then increase speed until the texture is smooth and slushy (about 30 seconds).
Taste test: adjust thickness with pineapple juice, sweetness with more cream of coconut, or add lime for balance.
Pour into glasses and garnish with a pineapple wedge, cherry, and umbrella if desired.
Serve immediately and enjoy the tropical vibes!