A couple weeks ago a former colleague of mine who had previously introduced me to the moka pot for brewing coffee sent me am image of a new coffee beverage he had discovered and instructions on how to make it. Basically an egg yolk and one or two teaspoons of sugar whipped into a foam then pour your espresso (or moka) into it. I have no idea what it's called but it's delicious. I just got a few duck eggs from a friend the other day so I might just try it with one of those and make a double

Sounds yummy.
I got the best results from cold brewed concentrates, my goto summer coffee method. It's a different level, not comparable to bitter steam or hot water brews.
But you need to have very good water and also good coffee, which needs to be ground at the most rough grain your coffee grinder offers.
I tried it once with ground filter coffee (Illy, though) off the can (they are sold in 250g cans), and i had to pour it away because the bad taste cut even through high amounts of milk.