Heat oven to 400 degrees. Wash the sweet potatoes and dry them well. Place 4 of the sweet potatoes onto a baking sheet and bake for 1 hour. Set aside to cool. Reduce heat to 375 degrees.
Start working on the pie crust after the potatoes are done. Spray a pie pan or 8 to 10 inch cast iron skillet with non stick spray. Set aside.
Peel the other two sweet potatoes and shred with a grater. Cover with cold water, then drain. Squeeze all excess water from the shredded potatoes. Using several paper towels, continue to squeeze and blot the potatoes until they are completely dry.
In a bowl, combine the shredded potatoes with ¼ teaspoon of the salt and one egg. Stir well. Transfer the mixture into the prepared skillet. With a spoon and your hands, gently press the crust mixture evenly onto the bottom and up the sides.
Bake the crust at 375 for 40 to 45 minutes until the edges are crispy and the bottom is firm. Remove from the oven and cool in the pan on a wire rack. Cool completely.
Peel the skins from the roasted sweet potatoes. Place in a bowl with the remaining ingredients. Using a hand mixer, beat on low to medium until the filling is smooth and creamy.
Pour evenly into the pie crust. Bake for 1 hour and 15 minutes. Allow to cool for 2 to 4 hours.