Combine kosher salt and dark brown sugar in a food processor or blender.

Process until well blended, ensuring no large granules remain.

Add chili powder, sweet spanish paprika, black pepper, cayenne pepper, garlic powder, taco seasoning, onion powder, dry mustard, ground cinnamon, ground nutmeg, curry powder, ground coriander, and ground cumin to the food processor or blender.

Process until all spices are well blended and uniformly distributed.

Add granulated sugar to the mixture.

Process until the sugar is evenly distributed throughout the spice blend.