Follow these simple steps to create your Sweet Potato Casserole Thanksgiving:

1. Preheat the Oven: Preheat your oven to 350°F (175°C).
2. Boil Sweet Potatoes: Peel and chop the sweet potatoes into chunks. In a large pot, cover with water and boil until tender, about 20-25 minutes.
3. Drain and Mash: Once the sweet potatoes are soft, drain them and return them to the pot. Mash them until smooth.
4. Add Ingredients: Mix in granulated sugar, softened butter, milk, eggs, vanilla extract, cinnamon, nutmeg, and salt. Blend until creamy and well combined.
5. Transfer to Baking Dish: Pour the sweet potato mixture into a greased 9×13-inch baking dish, smoothing the top.
6. Prepare Topping: In a separate bowl, combine brown sugar, chopped pecans, flour, and melted butter until crumbly.
7. Spread the Topping: Evenly sprinkle the topping mixture over the sweet potato layer.
8. Bake: Place in the preheated oven and bake for 30-35 minutes or until heated through and the topping is golden brown.
9. Add Marshmallows: If using mini marshmallows, add them on top during the last 5 minutes of baking, allowing them to melt slightly.
10. Cool Slightly: Remove from the oven and let it cool for a few minutes before serving.

Following these steps ensures that your Sweet Potato Casserole will turn out incredible every time.