Heat butter in a kettle over medium-high heat. Brown diced turkey on all sides; remove and set aside. Add crushed garlic cloves and sliced onions; stir over medium heat until golden. Add nutmeg, thyme, pepper, and beer. Simmer over low heat for 20 minutes.
In a bowl combine flour and cold water; slowly add to the hot mixture, stirring constantly until the sauce is thickened. Add baby carrots, sugar, and the browned turkey cubes. Bring to a boil; reduce heat; simmer for 10 minutes or until the turkey is cooked through.