Pour 1/2 cup of the water into a bowl and mix with yeast and sugar til foamy.
Let sit for 5 minutes until creamy.
Put the yeast mixture, rest of the water and 3 1/2 cups of the flour into the mixer with the dough hook.
Mix slowly until blended then add the rest of the flour.
Increase speed and scrape down the sides til the dough comes together.
(If it doesn't add a tbsp of flour at a time til it does.) Add salt and mix at medium speed for 10 minutes (or do half in mixer and half kneading) til dough is smooth and elastic.
Back in mixer add butter 1 tbsp at a time (dough may come apart, but mixing will pull it back together).
Turn dough out on lightly floured surface and shape it into a ball then place in a large buttered or oiled bowl.
Turn dough so it is completely coated in the fat, then cover in plastic for 45 minutes to an hour, til it has doubled in size at room temperature.
Butter 2 loaf pans.
Deflate the dough, cut in half and turn out onto a lightly floured surface.
Roll out into a 9 x 12-inch rectangle.
With the short end facing you, fold the dough into thirds like a sheet of paper to go into an envelope, creating a roll.
Pinch the seam closed, and pinch the ends enough so it will fit in the loaf pan.
Drop in the loaf pan seem side down, and repeat.
Cover the loaves with buttered plastic wrap and allow to rise again in a warm place (80°F) for 45 minutes, until they double in size.
Preheat the oven to 375°F and put the rack in the center of the oven.
Bake for 35-45 minutes til they are honey brown.
Immediately turn out of pans onto a rack to cool.
Once almost completely cool, they can be cut.
Store in a brown paper bag for a day or two.
Once cut, turn cut side down onto a cutting board and cover with a kitchen towel. ?