In a stand mixer add the water, milk, and yeast and let sit for 5 minutes until the mixture starts to foam. Add the flour and salt. Mix until the mixture becomes a shaggy mass. It will not hold together at this point.
Add the eggs and sugar. Mix on medium-low speed until the dough forms a ball. It will look a little dry. That is ok. Add the butter in half stick increments allowing each to completely incorporate into the dough. Once all of the butter has been added continue to mix for 10-15 minutes until the dough starts to pull away from the sides.
Transfer the dough to a clean bowl and cover with cling film and let rise for an hour. Knock the dough back down and cover that bowl again. Allow it to rise for 30 minutes and then knock down. Repeat this for the next 2 hours. Then cover and place in the refrigerator for 8 hours or overnight.
Place divide the dough in half, then divide each half into fourths. Place the 4 balls of dough in the tin, cover loosely with a towel and allow to double in size. You can also divide each half into thirds, roll the dough into ropes, and braid the ropes tucking the ends underneath before placing in the tin.
Preheat the oven to 350°F or gas mark 4. Mix the egg and cream together.
Lightly brush the tops of the loaves with the egg white and bake for 30 minutes or until golden brown. Allow to cool before slicing.