To make dressing, whisk together ranch mix, buttermilk, and mayonnaise in a bowl and refrigerate.
In a medium bowl, combine all 3 cheeses, mayonnaise, pimientos, onion, cayenne pepper, and bacon. Mix well and refrigerate 2-3 hours or overnight.
Form cheese mixture into 1 and 1/2 inch balls. Place milk, flour, and panko crumbs in 3 different bowls. Season flour and panko crumbs lightly with salt. Dip balls in flour, then in milk, and finally, coat with panko crumbs. Place on a tray and freeze for 1 hour.
Pour 2 inches of oil into a Dutch oven and heat oil to 350 degrees. Fry balls 4-6 at a time for about 2 minutes, then flip and cook another 2 minutes or until lightly browned and warm and gooey in the center. If needed, keep cooked balls warm in a 200 degree oven.