2 pounds sweet potatoes, peeled and cubed
1/2 cup melted butter
3/4 to 1 cup white sugar (depending on desired sweetness)
3 tablespoons all-purpose flour
1 teaspoon baking powder
2 teaspoon vanilla extract
2 tablespoons powdered sugar
Boil sweet potato cubes until tender. Drain and mash. Stir in melted butter.
Beat eggs until almost fluffy and add vanilla.
Add about 1/3 of the mashed potatoes to the egg mixture and quickly beat, so that the eggs don't cook. Add in remaining potatoes and stir. In a separate bowl, mix together remaining dry ingredients. Add to the potato mixture and beat well. Transfer into 2 quart baking dish.
Generously dust top with powdered sugar. This will make a crust on top, so don't be shy with the topping.
Bake in preheated oven for 30 minutes.