Dissolve the Kool Aid powder in hot water by stirring until fully combined and no lumps remain.
Pour the sweetened Kool Aid mixture into a blender.
Add the ice cubes to the blender, filling it up to about the second line for optimal blending.
Secure the lid and blend everything on high speed until the mixture is thick, slushy, and smooth, usually about 30-45 seconds. You should see the ice breaking down and the color brightening.
Pause briefly to check the consistency; if it’s too thick, add a splash of cold water or more Kool Aid and blend again for a creamier texture.
Taste a small spoonful to ensure the flavor is vibrant and the texture is icy but scoopable.
Pour the Kool Aid slushie into glasses or cups, garnishing with a slice of fruit or a colorful straw if desired.