In a mixing bowl, combine buttermilk and salt, creating a savory marinade. Submerge the whole chicken in this mixture, ensuring it's well-coated. Seal and refrigerate for a minimum of 4 hours, or up to 48 hours.

Preheat your oven to 390°F (200°C). Once marinated, remove the chicken from the mixture and let excess drip off, then place it on a parchment-lined baking tray.

In a small bowl, combine softened butter, minced garlic, and fresh herbs. Mix until well incorporated.

Pat the chicken dry and create small pockets in the skin. Spread the herb butter underneath and stuff the cavity with more herbs, smashed garlic, and a pierced lemon. Rub salt generously over the skin.

Place the chicken in the preheated oven and roast uncovered for 1 to 1 hour 15 minutes, rotating every 20 minutes until the skin is golden brown.

Check the internal temperature at the thickest part of the thigh should read at least 160°F. Once out of the oven, let it rest for 15-30 minutes before carving.