Basque Sheepherder's Bread

In a large bowl, combine hot water, butter, sugar, and salt. Stir until butter has melted; let cool to about 110 degrees. Stir in yeast, cover, and set in a warm place until bubbly (about 15 minutes). Beat in about 5 cups of the flour to make a thick batter. Stir in enough of the remaining flour (about 3 1/2 cups) to make a stiff dough. Turn dough out onto a floured board; knead until smooth and satiny (10 to 20 minutes), adding flour as needed to prevent sticking. Place dough in a greased bowl; turn over to grease top. Cover and let rise until doubled (about 1 1/2 hours). Punch dough down and knead briefly on a floured board to release air; shape into a smooth ball. With a circle of foil, cover the inside bottom of a 5-quart cast-iron or cast-aluminum Dutch oven. Grease foil, inside of Dutch oven, and underside of lid with salad oil. Place dough in Dutch oven and cover with lid. Let rise in a warm place until dough pushes up lid by about 1/2 inch (about 1 hour -- watch closely). Bake, covered with lid, in a preheated 375 degree oven for 12 minutes. Remove lid and bake for another 30 to 35 minutes or until loaf is golden brown. Remove from oven and turn out onto a rack to cool. Peel off foil and turn loaf upright. Makes 1 very large loaf.