Preheat the oven to 375 degrees F (190 degrees C).
Slice bread loaf using a serrated knife in a cross-hatch pattern. To do so, make vertical lines about 1 to 1.5 inches apart in one direction - slice almost all the way through, but leave about 1/2 inch intact on the bottom of the loaf. Then turn bread loaf 90 degrees and slice vertical lines about 1 to 1.5 inches apart in the opposite direction.
Stir melted butter, brown sugar, cinnamon and a small pinch of salt together in a small bowl until sugar dissolves in the warm butter. Taste and adjust here - if you’d like it a little sweeter, add more brown sugar in teaspoon increments.
Brush brown sugar-cinnamon butter between all of the bread slices with a pastry brush. Then, use a spoon to drizzle over any remaining brown sugar-cinnamon butter.
Wrap up the bread loaf in aluminum foil and place in an oven safe pot or on a sheet tray.
Bake in the preheated oven until well warmed through, 15 to 18 minutes.
Meanwhile, for vanilla icing, whisk confectioner’s sugar, milk (more milk results in a looser icing), vanilla extract, and a small pinch of salt together until sugar dissolves. Set aside.
Remove bread from the oven and unwrap the foil. Allow the bread to cool slightly, then simply pull out a slice. Bonus points if you dip in the icing for leveled-up deliciousness.
