In a large mixing bowl, whisk together bread flour, yeast, and salt until well combined.

In a separate medium-sized bowl, whisk together the 6 eggs, lukewarm water, and sugar. Continue whisking until the sugar is completely dissolved.

Slowly whisk in the melted and slightly cooled butter into the egg mixture until you achieve a smooth consistency.

Pour the wet mixture into the dry ingredients. Using a wooden spoon, stir vigorously until no traces of flour remain.

Cover the bowl with plastic wrap and let the dough sit undisturbed for 10 minutes.

Using your fingertips, gently fold the edge of the dough towards the center. Rotate the bowl slightly and fold again. Continue this process for a total of 8 times.

Once all folds are done, cover the bowl with plastic wrap again and let the dough rise for 30 minutes.

Repeat the folding and rising process (as steps 6 and 7) three more times, at 30-minute intervals.

After the last fold, seal the bowl tightly with plastic wrap and place it in the refrigerator for at least 16 hours.

Remove the dough from the refrigerator and transfer it onto a well-floured surface. Divide the dough into 4 equal pieces. Take one piece, pat it into a 4-inch disk, then fold the edges toward the center until a ball forms. Flip the dough over and, using a cupped hand, make small circular motions to form a smooth, taut round. Repeat with the remaining dough pieces.

Cover the shaped dough rounds loosely with plastic wrap and let them rest for 5 minutes.

Prepare two 8 ½ x 4 ½ inch loaf pans by greasing them thoroughly.

After the short rest, flip each dough ball over and repeat the folding and rounding step. Then, place two rounds, seam side down, into each prepared loaf pan, ensuring they fit snugly into the corners.

Cover the loaf pans loosely with plastic wrap. Allow the dough to rise in a warm location until it has doubled in size, roughly 1 ½ - 2 hours.

While the dough is rising, position a baking stone in the oven and preheat to 350°F.

Once the dough has risen, brush the top of each loaf gently with the beaten egg.

Place the loaf pans on the baking stone in the preheated oven. Bake for 35-45 minutes, or until the top is golden brown and the bread sounds hollow when tapped.

Remove the loaves from the oven and allow them to cool completely on a wire rack before slicing and serving.