Preheat oven to 275 degrees. Line a roasting pan with foil for an easier clean-up.
Clean chicken and pat dry.
Mix the mustard lemon juice (reserving the lemon halves), honey, chopped parsley, thyme leaves, and 1 clove of minced garlic in a bowl; rub mixture evenly over the entire bird.
Carefully, lift the skin over the breasts and rub the mixture directly on the breast meat.
Place onion and garlic inside the cavity along with some extra parsley, thyme sprigs, and reserved lemon halves. Season the bird evenly with sea salt and freshly cracked lemon pepper, to taste.
Place the chicken on the prepared roasting tray. Place the meat thermometer in the thickest part of the thigh, making sure not to touch the bone.
Roast uncovered for 3 1/2–4 hours until the meat thermometer reads 165-170 degrees. I start basting my bird after 2 hours and repeat every 1/2 an hour and my chicken turns out sticky and slightly crispy. Side Note: If you want crispy skin, don’t baste for the last hour, and turn the heat up to 350 degrees for the final 5 minutes of cooking.
Remove from oven and let the bird rest for AT LEAST 10 minutes before carving. Enjoy!