1. Heat the oven to 450 degrees.
2. In a small skillet melt the butter. Set aside to cool slightly
3. In a mini food processor or blender purée the garlic, chipotles, adobo lime juice until smooth.
4. With the machine running drizzle in the butter slowly until emulsified. Transfer the mixture to a bowl.
5. Pour the salt onto a baking sheet. Place the oysters, cup-side down, on the rock salt. Roast until the oysters begin to open, 8 to 10 minutes.
6. Working over the bowl of the butter mixture (to capture the oyster liquor) remove the oysters from the oven and open them. Use a butter knife or similar tool inserted into the hinge end and pry them open with a twist. Separate the muscle at the top and the bottom. Discard the top shells. Mix the contents of the bowl very well. This is your chiplotle butter sauce.
7. Drizzle about 1 teaspoon of the chipotle butter sauce onto each oyster.
8. Return them to the oven until the butter melts and the oyster plumps and firms, about 3 minutes. Serve immediately