Place the hot tap water, honey and yeast in a large lidded container (one that will hold at least 5 quarts - I use a food storage bucket). 

Mix well, add the eggs and stir again. 

Mix in the butter, salt and flour; stir well with a large wooden spoon or a large sturdy whisk until all the flour is incorporated.

Cover (not airtight), and allow to rest at room temperature until the dough rises and collapses (or flattens on top), approximately 1 ½ -2 hours. The dough can be used immediately after the initial rise, though it is much easier to handle when cold. Refrigerate in a lidded (not airtight) container and use over the next 5 days. Beyond 5 days, freeze in 1-pound portions in an airtight container or freezer-safe bag for up to 4 weeks. Defrost frozen dough overnight in the refrigerator before using. Then allow the usual rest and rise time.

When you're ready to start baking, oil the baking surface of a baking sheet. Remove half of the dough from the bucket onto a well floured surface. (I use one of these to transfer the dough, so handy!) Return the rest of the dough to the refrigerator if not using.

Turn the dough several times to coat well with the flour. Divide the dough into 3 equal pieces, using a dough scraper or knife. 

Again, turn each ball of dough to coat with flour, then roll the balls between your hands, stretching, to form each into a long rope. If the dough resists shaping, let it rest for 5 minutes and try again. The longer and thinner you make your "ropes" , the longer and thinner your finished loaf will be. If you want a plump, full loaf just leave your ropes a little shorter and fatter. I made mine about 14 inches long. Try to make each rope the same length.

Using wet hands, line up your three pieces of thin rope in front of you on a work surface. Braid the ropes, starting from the center and working to one end. Turn the loaf over, rotate it, and braid from the center out to the remaining end. This produces a loaf with a more uniform thickness than when braided from end to end. There is a very helpful tutorial on braiding bread here

Allow the bread to rest and have a second rise on the prepared cookie sheet for approximately 1 hour and 20 minutes (or just 40 minutes if you’re using fresh, unrefrigerated dough) or until puffy and doubled in size. Rising times will vary depending on your weather. 

Preheat the oven to 180C (350F). When dough is doubled in size, brush all over with the egg wash, then sprinkle liberally with sea salt. 

Bake near the center of the oven for about 25 minutes. Smaller or larger loaves will require adjustments in baking time. The challah is done when golden brown, and the braids near the center of the loaf offer resistance to pressure. 

Allow to cool on a wire rack before slicing or eating (if you can!).