Begin by pouring heavy cream into a mixing bowl. Using a hand mixer, whip the cream on medium speed until soft peaks form, which should take about 3-5 minutes. Transfer to refrigerator.

Brush the rims of your serving glasses with maple syrup, then dip into black sanding sugar. Set glasses in the freezer for about 10 minutes.

In a blender, combine vanilla ice cream, milk, black cocoa powder, maple syrup, and vanilla extract. Blend on high for 30-45 seconds until smooth.

Taste the milkshake and adjust flavor by adding more black cocoa if desired. Blend again for another 10-15 seconds.

Pour the blended milkshake into each glass, fill about three-quarters full, top with whipped cream, and add sprinkles. Serve immediately.