In a large bowl add flour, instant yeast, salt and sugar and mix.
Add melted butter and warm milk. Stir with a wooden spoon until wet dough is formed.
Cover and leave at room temperature for 5 minutes. After 5 minutes, mix again for few minutes, then again cover and let it rest for 45 minutes to 1 hour.
Grease a 9x5 loaf pan it with butter and lightly dust it with flour.
Punch dough with hands to remove all the trap air. Transfer the dough onto a lightly floured surface. Shape it into a loaf and place it in the prepared loaf pan. Cover the loaf pan with a damp towel and let it rest again for 15-20 minutes or until doubled in size.
Preheat the oven to 375F. Beat one egg with 1 tablespoon of water and brush on top of the bread.
Bake for 25-30 minutes or skewer inserted comes out clean.
Brush melted butter on top of freshly baked bread. Let it cool on the wire rack for 10-15 minutes before cutting.