Start by mixing your salt, sugar, garlic powder, onion powder, paprika, pepper, and turmeric in a small bowl. Set aside two tablespoons of this blend for the fries later. This step takes barely five minutes but shapes the flavor of your entire dish.
Pat your chicken completely dry using paper towels, since moisture on the skin prevents good browning. Rub some seasoning inside the cavity, then brush the outside with melted butter before coating it with the rest of the spice mix. Dry skin plus even seasoning is really the secret to that crackly, golden crust.
Place your chicken in a preheated 425 degree Fahrenheit oven and roast until the thickest part of the thigh reads 165 degrees Fahrenheit, roughly 90 minutes. Let it rest under foil for about 20 minutes once it's out. Resting locks the juices back into the meat instead of letting them spill out when you cut in.
While your chicken roasts, wash your russets and slice them into quarter-inch strips, keeping the skin on for texture and nutrients.
Heat your oil to 350 degrees Fahrenheit in a deep pot, then fry your potatoes in small batches so the oil temperature doesn't drop. Cook each batch for 10 to 15 minutes until deeply golden, stirring occasionally with tongs. Frying in batches keeps the oil hot enough for that shatter-crisp texture.
Once your fries come out of the oil, drain them on a paper towel-lined tray and immediately sprinkle with your reserved spice blend. The residual heat helps the seasoning stick right away. Plate your chicken alongside the fries and serve everything while it's still warm.