1- Peel and cube 3 pounds of sweet potatoes, then boil them until tender, which takes around 20 minutes.

2- Drain the sweet potatoes and mash them in a large bowl until smooth.

3- Mix in ½ cup packed brown sugar, ⅓ cup softened butter, ½ teaspoon vanilla extract, ¼ teaspoon cinnamon if desired, salt and black pepper to taste, and half of the ¾ cup chopped pecans.

4- Spread the mixture evenly into a greased 9 x 13-inch baking pan.

5- Top with 2 cups miniature marshmallows and the remaining chopped pecans.

6- Bake at 375°F for 25 minutes until the marshmallows are golden and the casserole is heated through.