Preheat the oil in a fryer or a heavy pan on the stove to 325℉.
Prepare a dredging station by putting flour in a medium bowl, and buttermilk in a separate medium bowl.
Coat the chicken breasts, one at a time, with flour, then submerge them in the buttermilk.
Coat the chicken breasts once more in the flour and set aside until ready to fry.
Fry the chicken breasts until golden brown and they reach a temperature of 165℉.
In a large bowl, add the Nashville Hot Sauce and the fried chicken. Toss the chicken until fully coated.
Place each chicken breast between two whole donuts, adding pickles (about 5 slices) on top.