In a food processor, combine macadamia nuts, bread crumbs, 1 teaspoon olive oil, black pepper, and red pepper flakes. Process until smooth. Preheat oven to 350 degrees F (175 degrees C).
In a small saucepan over medium heat, combine mango, cream, and lemon juice. Bring to a boil, reduce heat, and simmer until thickened.
Season fish with salt and black pepper. Heat 1 tablespoon olive oil and crushed garlic in a large skillet over medium heat. Sear the sea bass on both sides, and remove from heat.
Transfer fish to preheated oven, and roast until cooked through. Cover the sea bass with macadamia crust, and return to the oven until crust browns. Top with the mango cream sauce.