Chocolate Frosting Rim

1. Blend butter until light and fluffy.
2. With the mixer on low, add powdered sugar, cocoa powder, and heavy cream. Continue to mix on medium-high for about two more minutes, until combined.
3. Use an offset spatula or knife to carefully spread the chocolate frosting along the outside rim of each glass.
4. Pour sprinkles on a small plate and carefully roll each frosting covered rim in sprinkles, ensuring that they fully cover the frosting.
5. Chill glasses in freezer.

Whipped Cream

1. Combine heavy cream and sugar in a medium sized bowl. Mix on medium-high with a handheld or stand mixer until somewhat stiff peaks have formed. Cover and refrigerate until ready to use, slightly whisking before using if need be.

Assembly

1. Puree ice cream and milk in a blender for 10 seconds until thick and creamy.
2. Carefully pour the milkshake into each glass, making sure that it does not drip onto the chocolate covered rim.
3. Top each glass with a spoonful of whipped cream and more sprinkles.
4. Enjoy!