Brine the Chicken (Optional): In a large pot, combine water with sea salt and brown sugar, heating until dissolved. Add crushed garlic, thyme, and pepper; cool completely. Submerge the whole chicken into the brine, covering it well. Refrigerate for 12-18 hours.

Preheat and Prepare: Preheat your oven to 400°F (200°C). Rinse the brined chicken under cold water and pat it dry. Mix softened butter, olive oil, smoked paprika, garlic powder, sea salt, and black pepper. Rub this mixture under the chicken skin and all over the surface.

Stuff the Chicken: Stuff the cavity of the chicken with quartered onions, lemon slices, and crushed garlic cloves. Place the chicken in a greased roasting pan or Dutch oven, then pour in the chicken stock.

Roast the Chicken: Transfer the chicken into the oven and roast for 1 hour and 30 minutes. Baste halfway through and ensure the internal temperature reaches 165°F (74°C).

Make the Maple Cranberry Glaze: While your chicken is roasting, simmer maple syrup, cranberries, cranberry juice, and red pepper flakes in a saucepan over medium heat until the cranberries burst and the mixture thickens, about 15 minutes.

Final Glaze and Rest: Brush the remaining glaze over the chicken when roasting is nearly done. Remove from the oven, let it rest for 20 minutes before serving.