Using a stand mixer, mix together the sugar, butter, salt, water, and yeast. Let set for 5 minutes until nice and foamy.
Add the flour, 1 cup at a time until it forms a ball.
Turn onto a floured surface and knead for 8-10 minutes.
Place dough in a greased bowl, cover and let rise until doubled in size (about 30 minutes).
Punch down the dough, divide into 2 equal balls. Roll into a ball, and place side by side on a baking sheet. Cut cross slits in the top. Cover and let rice for another 30 minutes.
Preheat oven to 400 degrees.
Mix together the egg white and the water. Brush over the top of each ball of dough. Sprinkle evenly with salt and rosemary. Bake for 20-25 minutes. It will be golden brown and sound hollow when you tap on the bottom.