Madhur's Broiled Fish

INGREDIENTS

• 2 teaspoons finely grated ginger
• 3 cloves garlic, crushed
• 1 teaspoon garam masala
• 1/2 teaspoon ground cumin
• 1/4 teaspoon ground turmeric
• 1/2 teaspoon mustard powder
• 1/4 to 1/2 teaspoon cayenne pepper
• 2 tablespoons lemon juice
• Coarse salt and freshly ground pepper
• 5 tablespoons unsalted butter, melted
• 4 fish fillets or steaks (6 ounces each) such as swordfish, halibut, haddock, tuna, or salmon