1. Over a medium heat, sauté sausage until browned.
2. Add maple syrup and cook 1 minute, stirring until sausage is well coated with syrup.
3. Arrange in a single layer in a 13x9x2" baking pan.
4. Add a layer of frozen hash browns over sausage mixture.
5. In a medium bowl, mix milk, eggs, mustard and pepper, Pour this mix over hash browns.
6. Sprinkle cheese on top of this layer.
7. Start your Traeger on "MXedium". Bake mixture for 1 hour or until center of casserole set up.
8. Sprinkle on green onions.
9. Remove from grill, allow to cool for 10 minutes before cutting into squares.