01 - Combine milk, ice cubes, vanilla ice cream, vanilla bean seeds or extract, and sugar in a blender container.
02 - Process on high speed until completely smooth and creamy, approximately 45-60 seconds.
03 - Taste the mixture and add additional sugar if desired. Blend briefly for 10-15 seconds to incorporate.
04 - Pour evenly into two tall glasses. Top with whipped cream if using and serve immediately with straws.