Combine parsley, lemon peel, thyme, juniper berries, garlic, pepper and Tabasco in blender. Add oil, 1 tablespoon at a time, blending until a smooth paste is formed. Add lemon juice and blend. Rub mixture over surface of the roast. Cover and refrigerate for at least 24 hours.
Bring roast to room temperature before proceeding. Place roast in large heavy roasting pan and roast in preheated oven at 500 degrees for 15 minutes. Reduce temperature to 350 degrees and continue roasting for 15 minutes per pound for rare, 20 minutes per pound for medium, or 25 minutes per pound for well done. Let roast rest for 10 minutes before carving.