Preheat oven to 375 degrees F and grease a 9×13-inch baking dish.
In a large bowl, add sweet potato, brown sugar, half and half, butter, egg, vanilla, and salt. Beat with mixer until completely smooth.
Transfer sweet potato mixture to the prepared baking dish and spread into an even layer.
In a small bowl combine sugar, flour, pecan, and melted butter until a crumbly mixture forms. Sprinkle over sweet potatoes.
Bake for 35 minutes, then allow dish to cool for a minimum of 20 minutes before serving.