Preheat the oven to 450F, and line two baking sheets with parchment; set aside.
In a small cup, mix together the milk and vinegar and set aside.
In a large bowl, whisk together the flour, garlic powder, salt, and sugar. Mix in the melted butter and milk mixture until just combined, then gently mix in the cheese.
Scoop out ¼ cup portions of batter onto the baking sheet, setting them about 2-3 inches apart.
Bake for 10-12 minutes, until golden brown and fluffy.
Remove biscuits from oven, and while they cool, prepare the topping. Whisk together the melted butter, garlic powder, and parsley, and use a pastry brush to brush the tops of the biscuits.
Let cool slightly and enjoy!