Canning - at what point do I start the timer for a "boiling bath"
I've been canning for a couple of years now, but have a question regarding statements like these I find in recipes: "process in a boiling water canner for 15 minutes." At what point does the timer start for the 15 minutes? The water is boiling when I submerge the jars, but it usually takes 10 minutes for the water to return to a rolling boil. So does the timer start when I submerge them into the boiling water, or once the water returns to a boil. One of my recipes states "when it returns", the other does not. TIA! Sharon