1Heat oven to 350°F. In 2-quart casserole, mix half-and-half, boiling water and melted butter. Add 2 pouches potatoes and remaining potatoes ingredients; stir well.
2In small bowl, mix brown sugar and flour. With fork, cut in 2 tablespoons butter until crumbly. Stir in pecans; sprinkle over top.
3Bake uncovered 28 to 30 minutes or until topping is golden.