Crush salt, fennel seeds, cumin seeds, coriander and peppercorns with mortar and pestle. Rub venison on all sides with mixture. Cover and refrigerate overnight.
Preheat oven to 450 degrees. Pan sear until browned and transfer to oven to roast until medium rare, or desired degree of doneness. Transfer venison to work surface. Let stand 5 minutes. Cut into 1 inch thick slices. Arrange on platter. Spoon Habanero Sauce over. Sprinkle with green onions.