Bring about 10 cups of water to a rolling boil. Peel and cut your sweet potato into 1-inch cubes.
1 pound sweet potato
Add the cubed sweet potato to the water and boil for about 10 minutes or until sweet potato is fork-tender.
Meanwhile, make the crust. Add the flour, butter, brown sugar, and salt to the blender and blend on high for about 10-15 seconds, until the butter just starts to cut into the flour.
½ cup frozen unsalted butter, 1 ½ cups all-purpose flour, ¼ teaspoon salt, 1 tablespoon light brown sugar
With the blender on, add the cold water and blend for an additional 5-10 seconds until the blender starts to form a dough. It's okay if there is still some excess flour that is not well-combined. You will work it into the dough in the next step.
¼ cup cold water
Turn the dough out into your pie dish and use your hands to press the dough into the bottom of the dish, working in any excess flour. As you work the dough, use your fingers to push the dough up the sides of the dish, until you're left with an even layer of crust. Set the pie dish aside.
Clean your blender and strain the boiled sweet potato, getting as much water off as possible. Add the sweet potato to the blender with the butter, brown sugar, sweetened condensed milk, and pumpkin pie spice. Blend on high until smooth.
¼ cup unsalted butter, softened, ½ cup light brown sugar, 14 ounces sweetened condensed milk, ¾ teaspoon pumpkin pie spice
Add the egg to the blender and pulse 8-10 times to blend the egg into the filling without over-beating it.
1 large egg
Pour the filling into the prepared crust and bake on the top rack of the oven for 45-50 minutes until the filling is set. Option to add a little whipped cream (this Pumpkin Whipped Cream is especially delicious) on top. Enjoy!