Drizzle some chocolate sauce on the sides of the serving glasses and freeze them for 10-15 minutes. This step is totally optional though.
Add crushed Oreo cookies, Instant coffee powder, granulated sugar, chilled whole milk, milk powder, and ice cubes into the jar of a blender.
Adding a few ice cubes while blending the coffee makes it very frothy.
Blend for 1-2 minutes until the coffee is frothy.
Pour the frothy coffee into the prepared glasses.
Top with whipped cream and sprinkle some coffee powder on top. Garnish with Oreo cookies and serve immediately.