Heat milk, water, and 2 Tbsp butter to 110°F (or to warm but not hot)
Pour into stand mixer. Add sugar, salt, and yeast. Allow yeast to sit and "bloom" for 10 minutes or until foamy and smells yeasty.
Turn mixer on low. Slowly add flour.
Dough should pull away from the sides of the bowl and no longer be sticky to the touch.
Cover and allow to rise until doubled, about 1 hour.
Roll dough out on floured surface into a 12 x 12 inch square (no need for perfection just approximate)
Cut dough into 16 equal(ish) squares.
Melt remaining 2 Tbsp butter, and brush dough with melted butter.
Grease loaf pan with cooking spray.
Placing one piece of dough in pan with buttered side towards the edge of the pan.
Then butter the dry side of the dough in the pan (see pictures). Repeat with remaining pieces of dough.
Cover and allow to rise 1 more hour or until doubled in size.
Bake at 375° for 30 minutes or until deep golden brown (if top gets too dark before the inside is done, cover with foil and continue baking until cooked through).
Remove from loaf pan and serve hot or wrap in plastic wrap, refrigerate and reheat before serving.