Creme brulée heating milk
you need to temper the eggs, which basically means pre-ccoking them slightly so they can withstand the higher temperatures of the oven without curdling. getting your cream to the simmering point then whisking it into the eggs achieves this goal. there is no need whatsoever to let things cool down; bring cream to boil w/whatever flavourings you're using (e.g. vanilla beans), pour in a slow but steady stream into a bowl of your whisked-to-pale-yellow-ribbon egg yolks &amp; sugar, pour through a very fine mesh strainer, skim off any foam, pour into ramekins, bake. 

(For reference, I've made approximately five thousand creme brulees in the last year, this is the method I use every time).