Help me settle a long-running question in my house. My wife says that for cooking, water should always be boiled starting with cold water. Apparently professional cooks do this and the Martha Stewart, Julia Child, etc. types also say it. This is for things like boiling eggs, cooking pasta, etc. where the water is heated completely alone, not as part of the actual cooking process with other ingredients involved.

I say that if you already have warm water at the tap (for example if you were just washing dishes) you can just use that and it might even save a little energy. (If the warm water in the pipe is just going to sit there cooling off anyway, might as well use it. Plus hot tap water must be more efficient than heating a pot over an open flame, right? We have natural gas for both hot water and the stovetop.)

The end result will be boiling water, why would it matter if it started off cold or warm? It's all H20 just with varying amounts of energy.

I start with hot tap water (already a little over 1/2 way to boiling) and it boils much faster (obviously) than waiting for cold tap water to heat, especially since our water is well water, much colder than standard tap water.