Measure and combine all ingredients in a small bowl, stirring well until they become uniform.
Rub ½ cup of seasoning mix per 10 lbs of meat. (You can work in the seasoning using olive oil for a neutral taste, or soy sauce to make it more flavorful.)
Add seasoning until you have the desired amount, making sure to coat all sides of the roast.
Place the mixture in a large dish covered in plastic wrap in the refrigerator and allow it to soak into the meat for at least 24 hours before cooking.