Brew the coffee using either a traditional Vietnamese coffee filter, or contraption of your choice.
Crack 2 eggs and set aside whites for another purpose.
In a small bowl add the yolks and condensed milk and whisk until thick and creamy. I suggest using electric beaters for this.
Stop whisking when the egg mixture is the consistency of custard.
Divide the hot coffee between 2 glasses, then pour the egg mixture on top. It will float to the surface and sit on top of your coffee like a nice sweet blanket.