Gather all your ingredients and equipment.
In a blender, add the chocolate ice cream.
Pour in the milk.
Add the chocolate syrup for extra flavor.
Blend the mixture on high speed until smooth.
Check the consistency; add more milk if you prefer a thinner shake.
Pour the milkshake into two tall glasses.
Top with whipped cream generously.
Drizzle some chocolate syrup over the whipped cream.
Optionally, sprinkle chocolate shavings on top for decoration.