Preheat your dutch oven or conventional oven to 425°.
Combine butter, garlic, pecorino romano, and salt then mix.
Pour 1/4" of rock salt it the bottom of a dutch oven (or sheet pan if cooking in oven).
Shuck oysters removing top shell. Be sure to loosen oyster from bottom shell with the oyster knife.
Arrange oysters on dutch oven and lightly press into rock salt to keep oysters from tipping.
Spoon the mixture onto each oyster and cover. Let mixture melt 1-2 minutes.
Sprinkle jack cheese on and cover. Cook 4-5 minutes until cheese is melted and begins to brown.
