Preheat the oven to 375 F.
Rinse your oysters in cold running water.
Put oysters on a cooking sheet with a shallow part of a shell on top and deep shell side on the baking sheet, and put in the oven for 3-5 minutes, until the oysters start opening up a little.
While your oysters are in the oven, melt butter over medium-high heat. Once melted, add grated garlic and mix well.
Take oysters out of the oven and let them cool until easy enough to handle. Wrapping one side of a kitchen towel around your hand and the other side around your thumb, carefully open each oyster with a knife, while preserving the liquid inside the oyster.
Place shucked deep-shell sides of oysters on a baking sheet. Spoon 1 teaspoon of garlic butter on each oyster and sprinkle with 1 teaspoon of parmesan cheese.
Place the baking sheet in the oven and cook for 6–8 minutes. After the cheese has melted, switch the oven to broil for 1-2 minutes, keeping a close eye on the oysters to prevent them from burning. Do not overcook. Remove from the oven when the cheese turns golden brown and serve immediately.
Enjoy!