beat 180 g flour, yeast, water and eggs until smooth using mixer and beater attachment. let it sit for 45 minutes covered with a towel.
add the 150 g left over flour, sugar and salt
beat using dough hook for 8-10 minutes
add butter 2 tbs at a time, beating in before adding more
let it rise 1 hour, covered
fold the dough a few times and place in a greased bowl, it might be a bit sticky. refrigerate 4-16 hours.
shape the dough into balls and place in your greased loaf pan
allow to rise for 1 and half hours- it should look puffy
preheat oven to 375
whisk equal parts egg and water to make an egg wash, brush loaf with this
place loaf pan on a double layer of sheet pans and pop in oven for 20 minutes
either cover loaf with foil tent or place sheet pan on rack above loaf to prevent browning. bake for another 20 minutes. i deep brown crust is a good, traditional thing, but watch out for burning! the inside of the bread should get to 190 degrees.
cool for 10 minutes in pan, then release it from pan and let it continue to cool on rack (or pull it apart at this point like cookie monster attacking a cookie)