Preheat oven to 400 degrees.

Scrub the sweet potatoes and prick them several times with a fork. Place on a foil-lined baking sheet and roast for 40 minutes or until fork tender.

Remove from the oven and let cool for 5 minutes.

Reduce the oven to 350 degrees.

Scrape the sweet potatoes out of the skin (4 cups) and place them into a large mixing bowl. Add the milk, eggs, sugar, melted butter, salt, vanilla, and pumpkin spice. Using an electric mixer, beat on medium speed for 3-4 minutes until smooth.

Spread the filling into a 9x9 baking dish.

In a small bowl, add the brown sugar, flour, pecans, and softened butter, and using a fork, blend until crumbs form.

Spread the topping evenly over the sweet potato mixture.

Bake for 40 minutes, tent with aluminum foil if starting to get too brown on top.