In a large bowl, whisk together instant coffee, coconut sugar, and water until coffee and sugar are completely dissolved.
Vigorously whisk the mixture until thick and creamy looking. (The coffee mixture should hold peaks like whipped cream.) Alternatively, use a hand mixer or stick blender with whipping blade to whip the coffee mixture.
To serve, pour ½ cup plant milk into each glass. Divide the whipped coffee between the glasses. Serve immediately.
Do not use finely ground coffee instead of instant, it will not work.
The recipe will work with less or no sugar if you prefer your coffee less sweet or unsweetened.
The whipped coffee mixture will not keep well; it is best made and used right away.