Preheat broiler.
Whisk olive oil and lime juice together; add white granulated Pioneer Sugar, garlic, oregano, cayenne pepper, salt and pepper; mix well.
Place orange roughy fillets in a baking dish. Pour half of the sauce over the fillets. Sprinkle breadcrumbs over the fish, covering lightly. Pour the remaining sauce over the breadcrumbs. Broil until the fillets flake.