Preheat the barbecue to medium heat. Layer 2 sheets of tin foil about 12-inches long. Repeat. Divide and place the crab in the centre of each piece of layered foil. Combine the remaining ingredients in a bowl and spoon over the crab. Pull up the corners of the foil to form a packet; fold at the top to seal. Set on the barbecue, close the lid and cook just until the crab is heated through, about 5 to 8 minutes.
Recipe Options: Make this dish Italian in style by using extra virgin olive oil instead of butter and sprinkling in a mix of chopped fresh herbs, such as oregano, basil and Italian parsley. To give the crab Asian-style flare, replace the butter mixture with this mixture combined in a bowl and spooned over the crab: 1/3 cup orange juice, 2 Tbsp. soy sauce, 1 tsp. wasabi powder, 2 tsp. freshly grated ginger,1 garlic crushed cloves and 2 finely chopped green onions.