Step 1

Place turkey roast in a roasting pan or a nine- by 13-inch (20- by 30-centimeter) baking pan.

Step 2

Mix together all sauce ingredients and pour over the turkey.

Step 3

Heat olive oil in a large frying pan. Add onion and sauté five minutes over medium heat. Add sweet potato cubes and continue sautéing 15 minutes more, stirring occasionally. About one to two minutes before the end, add the garlic. Remove from heat. Season with kosher salt and pepper. Cool slightly.

Step 4

Carefully spoon veggies over turkey roast, pressing down gently so they stick. Cover and marinate in the fridge overnight.

Step 5

Preheat oven to 350 degrees Fahrenheit (175 degrees Celsius).

Step 6

Cover turkey with Gefen Easy Baking Parchment Paper and seal tightly with aluminum foil. Place in oven and bake for two hours and fifteen minutes. Baste once or twice during baking. Uncover and continue baking an additional five minutes. If necessary, add a little hot water to the pan. Cool completely before slicing.