A perfectly-cooked poached or fried egg is fantastic on pretty much anything — from ramen to burgers — but, be honest, you're mostly just in it for the yolk. You could cook individual eggs to that perfect, runny-yolk stage, or you could make this yolk sauce from Cook's Science and use it all week. As explained in the video above, what makes egg yolks so delicious is the fact that they are naturally occurring emulsions of water and fat. (Other notable, but not naturally occurring emulsions include butter and mayonnaise.) Since the egg yolk is so tasty on its own, all you need to make this "sauce" are the yolks themselves and a little salt. Just mix a few separated yolks together with a couple of pinches of salt, pour into a sealable plastic bag or mason jar and submerge in a constant temperature water bath set to 65C for 32 minutes.
This pasteurises the yolks and cooks them to that perfect "runny" point. Pour that liquid gold in a bottle (store it in the fridge, where it will keep for a week) and drizzle on everything you would normally put an egg on.