Preheat oven to 425°F. Scatter carrots and onions in a roasting pan. Toss with a tablespoon of Challenge Spreadable Butter and a pinch of salt and pepper.
Season the chicken cavity with salt and pepper, then stuff with lemon slices, garlic and fresh thyme. Use kitchen twine to truss the chicken; place it in the roasting pan.
Season outside of chicken with salt and pepper then spread all over with ¼ cup of Challenge Spreadable Butter.
Roast chicken for 30 minutes, then spread with remaining 2 tablespoons Challenge Spreadable Butter. Reduce oven temperature to 350°F. Continue to roast, basting every 15 minutes, for another hour or until an instant-read thermometer registers 165°F.
Transfer the chicken and vegetables to a platter and tent with foil for about 15 minutes. Slice the chicken and serve with the vegetables.