I have seen it being made on TV it looks delicious. I'm afraid of raw egg so I made it once just by whisking the condensed milk; deliciousI was in Vietnam in December 2019, I was invited to try "Vietnamese egg coffee".
Vietnamese egg coffee is made by beating an egg yolk with sweetened condensed milk for about 8 ~10 minutes until it makes an airy, creamy, meringue-like fluff.
View attachment 208943
I like it very much. Have you tried it?