Prepare the pineapple by cutting it into small, manageable chunks to help the blender process smoothly.
Add the pineapple chunks and ice cubes into the blender, ensuring an even distribution for smooth blending.
Pour in the sweetened condensed milk if you're using it; this adds richness and a creamy texture.
Blend everything on high speed until the mixture is completely smooth and frosty, with no large ice pieces remaining.
Stop the blender and check the texture—if it's too thick, add a little water or juice and blend again to loosen it slightly.
Pour the slushie into glasses, and if desired, garnish with a small pineapple wedge or a sprig of mint for an inviting presentation.
