In a large mixing bowl add the turkey, sage, 1 tsp salt, and 1/2 tsp pepper and mix until combined
Add the turkey mixture to a medium saucepan over medium heat and cook, while breaking up the turkey into small pieces, until turkey is cooked through, about 6 minutes.
Add the butter and when the butter has melted add the flour and stir until well combined.
slowly stir in the milk. Reduce heat to medium-low and simmer, stirring often, until thickened to desired consistency. Season with extra salt and pepper to taste, if necessary.