Combine the sweet potatoes, whole milk, heavy cream, sugar, cinnamon, and nutmeg in a large pot. Weigh the pot and all the ingredients and the pot together and write down the number in grams. Heat the pot over high heat till it boils, stirring continually and then reduce to medium low- low to keep a light simmer. Scrape the bottom and sides with a rubber spatula to keep the milk from burning. Simmer till sweet potatoes are tender and the contents of the bowl weighs 530-540 g less than it did when you put it on the stove. (If you don’t have a scale, you can measure the contents and it should come to about 3 2/3 cup total in volume). It will take about 30 minutes or more. Don’t cook above a simmer or the milk could curdle or burn.

Preheat oven to 350 F

Remove from heat and add vanilla extract and salt. Using an immersion blender, blend till smooth. Add eggs and blend again till smooth. (or in just a normal blender)

Pour pie filling into baked pie shell and place on a rimmed baking sheet. With foil, tent the sides of the crust so they don’t burn. Place in oven and bake for about 35-40 minutes till the center of the pie is lightly set in the middle. (If you have a thermometer, bake till the center registers at 195 F.) Cool at room temperature at least 25 minutes before cutting.

Top with Whipped cream, if desired.