Mix zest, salt, 2 teaspoons thyme, pepper and sugar. Rub onto both sides of steak, coating evenly. Let sit at room temperature up to 1 hour.
Preheat a grill or oven broiler to high. Place steak on wire rack over sheet pan if using oven. Cook 8 minutes. Turn and cook 6-8 minutes more for medium-rare to medium.
Let sit 10 minutes before slicing.
Place oil in saucepan over medium heat. Add shallot and remaining thyme. Cook 3 minutes. Add 1/2 cup orange juice. Simmer 4-5 minutes to reduce. Stir in soy sauce. Lower heat. Whisk in butter to thicken. Season with salt as desired.
Slice steak thinly and serve with sauce.
*A Stetson Original fragrance note! GO BOLD: Add 1 teaspoon crushed Aleppo or Szechuan pepper to the dry rub to add spicy heat to the steak.