In the bowl of an electric stand mixer fitted with the dough hook attachment, add warm water. Sprinkle yeast over the water, then sprinkle the sugar over the yeast. Let the yeast proof in the water with the sugar until it's frothy, about 10 minutes. Add melted butter, salt, and 3 1/2 c. flour and mix until incorporated. With the mixer running, gradually add 3 to 3 1/2 cups more flour until the dough comes together in a cohesive ball that clears the bottom and sides of the bowl and doesn’t leave a lot of doughy residue on your fingers when touched. It will still be just slightly tacky (you don't want it to be overfloured and dense).

Knead in the mixer on a medium speed for 6 minutes. Cover bowl and let dough rise in a warm place until the dough has at least doubled in size, about one hour.

Punch dough down and divide it into two equal pieces.

Grease two 8 1/2-inch by 4 1/2-inch bread pans.

Form each piece of dough into a thick rectangle about 8-inches long; roll it up, pressing on the seams, and pinching the final seam together.

Place the dough loaves into the prepared pans, seam side down.

Let rise until doubled and the dough has risen about 1-inch above the top rim of the pan, about an hour or so, depending on the temperature of your house.

Bake at 350 degrees Fahrenheit for about 30 minutes until golden. Remove bread from oven and immediately remove it from the pans. Rub butter over the tops of the hot loaves, if desired. This will soften the crust. Let cool at least until it won't burn your mouth and slice.

The bread can be stored at room temperature, in an airtight bag, for a couple days, or frozen for up to a month or so.