- 1 tablespoon whole black peppercorns
- 2 teaspoons whole coriander seeds
- 2 teaspoons mustard seeds
- 2 teaspoons dried rosemary
- 1/2 teaspoon dried crushed red pepper
- 1 teaspoon plus 1 1/2 cups coarse kosher salt
- 1 30-ounce porterhouse or T-bone steak (about 2 to 2 1/4 inches thick)
Mix first 7 ingredients in small bowl. Transfer 2 tablespoons spice mixture to spice grinder; grind finely. Mix in 1 teaspoon salt. DO AHEAD Can be made 1 week ahead. Store whole and ground spice mixtures separately in airtight containers at room temperature. Rub ground spice mixture all over steak. Wrap in plastic; chill 3 hours.
Preheat oven to 475°F. Unwrap steak; place in large ovenproof skillet. Mix whole spice mixture with 1 1/2 cups kosher salt in medium bowl. Add 1/4 cup water; stir to moisten. Pack salt over top and sides of steak. Roast until instant-read thermometer inserted horizontally into steak registers 130°F for medium-rare, about 25 minutes. Let stand at room temperature 8 minutes. Crack salt crust with wooden spoon; discard. Turn steak over. Slice into 1/2-inch-thick slices.