Open the can of coconut milk. If the contents have separated (which they tend to do), go ahead and mix them really well in a bowl–I usually just use a fork and treat the mixture like eggs and whip-away until it’s all smooth.
Add the sugar and vanilla (if in bean form, please pulverize it first, though…whole vanilla bean just won’t work) to the well-mixed coconut milk and mix well.
Pour the mixture into an ice cube tray (or two…I don’t let any of this goodness go to waste!). You can also use just a baking sheet or something else thin and flat, but the ice cube tray makes it so much easier to pop in the blender.
Freeze until solid (this may take a couple of hours, but be patient–it’s worth the wait).
Place frozen chunks in the blender and blend, baby, blend! If it seems like it needs some liquid to help it along, you can microwave 1 cube (approximately 2 tbspn) until it’s liquid again and put that in the blender, but do not put water in there!
Just before it’s all thoroughly smooth and very much a Frosty, that’s when you add the little bit of chocolate. I guess you could put more chocolate in it, but if you’re going for that delicate balance like the real Frosty, you can believe me that just a little bit goes a long way!
Place in a fancy cup and enjoy!