Add the instant coffee, sugar and hot water to a bowl.
Using a handheld mixer, whip on high for 2–4 minutes, until pale, thick and glossy with stiff peaks.
In a glass, whisk together the condensed milk and milk until smooth.
Fill with as much ice as you like.
Spoon the whipped Dalgona coffee over the top.
Add a splash of cold brew if you want it stronger, then stir everything together until creamy and frothy.
