In a small bowl, mix together paprika, dry mustard, cayenne pepper, cumin, black pepper, white pepper, thyme and salt; set aside. Heat a heavy cast iron pan on high heat until extremely hot, about 10 minutes.
1 tablespoon paprika, 2 teaspoons dry mustard, 1 teaspoon cayenne pepper, 1 teaspoon ground cumin, 1 teaspoon black pepper, 1 teaspoon white pepper, 1 teaspoon dried thyme, 1 teaspoon salt
