Use a Makeshift Double Boiler for Foolproof Pasta Carbonara
by A.A. Newton on Skillet, shared by A.A. Newton to L from Lifehacker on (#54J2P)

Emulsifying hard cheese and pasta water into a perfectly smooth sauce is basically a graduate-level course in Pasta Thermodynamics. The pan must be hot enough to melt the cheese evenly, but not so hot that it seizes-or, in the case of pasta carbonara, you wind up with a big bowl of scrambled eggs.