In a small bowl, mix the softened butter with minced garlic (or garlic powder), parsley (if using), and a pinch of salt and pepper to create a garlic butter spread.
Heat a skillet over medium heat.
Spread one side of each slice of bread generously with the garlic butter mixture.
Place two slices of bread butter-side-down in the skillet.
Sprinkle half of the shredded cheese evenly on top of the bread in the skillet.
Place the remaining slices of bread on top, butter-side-up.
Cook for 3-5 minutes until the bottom is golden brown and the cheese starts to melt.
Carefully flip the sandwiches using a spatula, and cook for another 3-5 minutes until the other side is golden brown and the cheese is fully melted.
Remove from the skillet, slice in half, and serve warm.