In a large mixing bowl, combine 2 cups of warm water (about 110°F) with 4 teaspoons of instant yeast and 1 cup of sugar. Stir gently and let it sit for about 5-10 minutes until it becomes frothy.
Once the yeast is activated, add 1 tablespoon of Kosher salt and 3 tablespoons of cubed unsalted butter to the yeast mixture. Begin incorporating flour, starting with 9 cups of all-purpose flour.
Transfer the dough onto a lightly floured surface and knead for about 8-10 minutes, adding flour gradually until the dough is smooth and elastic.
Place the kneaded dough in a greased bowl, turning it to coat all sides. Cover it with plastic wrap or a clean kitchen towel and let it rise in a warm place until it doubles in size, about 1-2 hours.
Once risen, punch the dough down gently to release excess air. Divide the dough into two equal portions. Shape each portion into a loaf by flattening it into a rectangle, then rolling it tightly from one end to the other. Pinch the seams to seal.
Place the shaped loaves into greased loaf pans. Cover them again and let them rise until they’ve doubled in size, about 30-45 minutes.
While the loaves are rising, preheat your oven to 375°F (190°C).
Once risen, brush the tops of the loaves with the melted unsalted butter to give them a lovely golden color. Bake in the preheated oven for about 30-35 minutes or until the bread sounds hollow when tapped on the bottom.
Remove the loaves from the oven and let them cool in the pans for about 10 minutes. Then, transfer them to a wire cooling rack to cool completely before slicing.
