In a high speed blender, add your milk, condensed milk, and crushed ice, and blend until combined. Add your avocado and continue to blend until creamy and smooth.
Pour the smoothie into four glasses and enjoy immediately.
* You can substitute this for 2 tablespoons of your favorite granulated sweetener.** You can use pre-frozen avocado chunks. TO STORE: This smoothie is best enjoyed fresh, as it can separate the longer it sits. However, if you intend to drink it within 24 hours, you can store it in the refrigerator, covered. Before drinking, give it a stir using a spoon. TO FREEZE: Freezing smoothies is actually possible! Freeze this smoothie in a shallow container or in an ice cube tray. The smoothie can be stored like this for up to 6 months. When ready to enjoy your smoothie, simply remove it from the freezer and place it back into your blender and blend until it is smooth and creamy.