Add 2 cups of lemonade to a blender followed by half the frozen pineapple. Pulse to blend
Add the remaining 1/2 cup lemonade and half of the remaining frozen pineapple. Pluse to blend.
Add the remaining frozen pineapple and blend. Then puree to make smooth.
NOTE: if needed add more lemonade or make the frozen lemonade in batches to not over heat the blender motor.
Make the recipe larger or smaller using a 1:1 ratio of prepared lemonade to frozen pineapple. Always put the lemonade in the blender first and less of the frozen pineapple to allow it to blend and not over tax the motor before adding more.