Creating Easy Sweet Potato Casserole is straightforward when you follow these simple steps:

1. Preheat your oven to 350°F (175°C).
2. Prepare Sweet Potatoes: Peel and chop sweet potatoes. Boil them in a large pot until tender, about 15-20 minutes.
3. Mash Sweet Potatoes: Drain and mash the sweet potatoes in a bowl until smooth.
4. Mix Ingredients: In a large mixing bowl, combine the mashed sweet potatoes, granulated sugar, softened butter, milk, eggs, vanilla extract, cinnamon, and nutmeg. Mix until well combined.
5. Transfer to Baking Dish: Pour the sweet potato mixture into a greased 9×13-inch baking dish, spreading it evenly.
6. Prepare Topping: In a separate bowl, mix brown sugar, chopped pecans, flour, and melted butter until crumbly.
7. Add Topping: Sprinkle the topping evenly over the sweet potato mixture.
8. Optional Marshmallows: If desired, add mini marshmallows on top of the casserole.
9. Bake: Place the baking dish in the preheated oven and bake for 30-35 minutes, or until golden and bubbly.
10. Cool Slightly: Once done, remove from the oven and let it cool for a few minutes before serving.

These easy-to-follow steps will guide you in creating a delicious casserole that everyone will love!