Pecan Sweet Potato Casserole

1 large sweet potato, peeled and cubed
2 tablespoons sugar
2 tablespoons 2% milk
2 tablespoons beaten egg
1 tablespoon butter, melted
1/4 teaspoon vanilla extract

2 tablespoons chopped pecans
2 tablespoons brown sugar
1 tablespoon all-purpose flour
1 tablespoon butter, melted

Place sweet potato in a small saucepan and cover with water. Bring to a boil. Reduce heat; cover and cook for 20-25 minutes or until tender. Drain. Place potato in a bowl; mash. Stir in the sugar, milk, egg, butter and vanilla until blended. Transfer to a 3-cup baking dish coated with nonstick cooking spray. Combine topping ingredients; sprinkle over sweet potato mixture. Bake, uncovered, at 350 degrees F for 25-30 minutes or until heated through.