In a medium mixing bowl, combine 1/4 cup of instant coffee, 1/4 cup of sugar, and 1/4 cup of boiling water.
Using a whisk or an electric mixer, whip the mixture until it becomes light and fluffy. This can take about 2-4 minutes with an electric mixer or about 8-10 minutes by hand.
In your serving glass, fill it with hot or cold milk (dairy or non-dairy options work great). You can also add ice if you prefer an iced version of Dalgona Whipped Coffee.
Spoon the whipped coffee mixture over the milk. You can use a spatula to smooth it out for a beautiful presentation.
Before drinking, mix the whipped coffee into the milk for a perfect blend of flavor. Sip and enjoy your delicious Dalgona Whipped Coffee!