Using a serrated bread knife, cut the baguette lengthwise and apply the softened butter to both sides.
Sprinkle each side of the baguette with garlic parsley salt, followed by the shredded cheese.
Turn the oven to a low broil. Place the baguette halves next to each other on the baking sheet and bake until the cheese turns golden brown and bubbly (about 5 minutes).