In a mixing bowl add 2 cups of flour, sugar and yeast. With a hand whisk or a fork, stir to combine.In a small saucepan, add the water, milk and butter and heat over low flame until lukewarm (~ 110F).Slowly pour over the flour mixture, stir to combine and let it rest for about 10-15 minutes until the sticky dough starts to rise and gets a spongy texture.Attached the dough hook to your mixer. With the mixer on low speed, start mixing the sticky dough, slowly beating the lightly beaten eggs in. Stir in the salt and slowly adding the remaining 2 cups of bread flour.When all the flour is added, increase the mixer speed to medium-low and let it knead for about 5-6 minutes or until the dough cleans itself from the sides of the bowl.If it's still sticky add just a little bit more flour. The dough should be soft and elastic.With greased hands, remove the dough from he mixing bowl and it into a buttered bowl, cover with plastic wrap and let it rise at room temperature until doubled in volume. It should take little over an hour.When the dough is risen, place it on a lightly floured surface, divide into 3 and roll each piece into a 15-inch rope.Braid the ropes, pinching the ends and tuck them under to seal.Gently place the braid on a baking sheet. If it's easier for you, you can braid it directly on the baking sheet.Cover with plastic wrap again and let it rest for the second time for about half an hour.Meanwhile, heat the oven to 400F.Just before placing the bread into the oven, brush it with the egg wash (1 egg yolked mixed with few drops of milk).Bake for 30 minutes or until nice and golden.Let it cool before slicing.