Mix buttermilk and pickle juice in a medium mixing bowl and add skinless chukar breasts. Allow to marinate for a minimum of 2 hours but, ideally, no more than 24 hours.
When ready to cook, heat 1/2 inch of peanut oil in a large skillet to 400 degrees Fahrenheit.
Toss each breast through flour and add to oil. Lightly salt and pepper. Do not crowd pan. Make sure oil stays around 400 degrees.
Flip once underside is golden brown. Pull once both sides are golden brown.
Add fried breasts immediately to bottom bun to soak up drippings. You’ll likely need three breasts per sandwich. Top with three thick pickles. Add top bun. Serve immediately.