In a spice grinder or small food processor; measure and add in the dried buttermilk, 2 tablespoons dried parsley, 1 teaspoon dried dill. Place the remaining 1/2 tablespoon parsley and 1 teaspoon dried dill and set off to the side. Measure and add in the onion powder, dried onion flakes, kosher salt, sugar, paprika, cayenne, salt and pepper. Turn on the processor and let it run until all the spices are blended into the buttermilk powder.
Transfer the ranch mix into a jar or container {that has a tight-fitting lid} and add in the reserved parsley and dill. Whisk to combine.
Notes
*You can omit the buttermilk powder if you would like to use fresh buttermilk, in place of milk when you prepare the dressing