Pre-heat oven to 325ºF (163ºC).
In a large pan, on medium-low, heat butter and sauté onions until transparent. Add garlic, sage and cranberries. Sauté for three minutes more or until cranberries are softened. Stir in rice, season with salt and pepper and set aside.
Place turkey breast flat skin side down. Place a piece of wax or parchment paper on top and flatten with the flat side of a meat mallet or a rolling pin until turkey breast is of fairly uniform thickness.
In a small bowl, combine maple syrup and butter well. Remove wax paper and spread 1/4 cup of the butter mixture on the inside of the turkey breast. Spoon the stuffing mixture on breast leaving a two inch border around the sides. Starting at one end, fold the turkey breast around the stuffing, fully enclosing the stuffing and secure with string or skewers.
Lay the carrots in the bottom of a lightly oiled roasting pan. Place the turkey breast seam side down on the carrots and rub with another 1/4 cup of the butter mixture. Season with salt, pepper and dried sage then cover and bake for 30 minutes. Uncover and continue to bake for 1 hour or until a meat thermometer registers 180ºF (85ºC).
Let turkey rest five minutes. In the meantime, heat remaining butter and maple syrup on medium heat until mixture begins to boil and starts to reduce. When mixture appears thickened remove from heat. Remove string or skewers from turkey breast and slice in 1 inch thick slices. Serve with roasted carrots and maple sauce.
Serves 4 to 6