Silky Sweet Potato Pie

Ingredients

• 16 ounces peeled, roughly diced sweet potatoes , from 2 medium sweet potatoes
• 1 vanilla bean, split and scraped, seeds reserved for whipped cream topping
• 2 or 3 cinnamon sticks
• 1 whole nutmeg
• 26 ounces milk , any percentage will do
• 6 ounces heavy cream
• 7 ounces white or lightly toasted sugar
• 1 tablespoon ground cinnamon
• 1 teaspoon freshly grated nutmeg
• 1/2 teaspoon Diamond Crystal kosher salt; use half as much if iodized
• 1/2 ounce vanilla extract
• 3 large eggs
• Old-Fashioned Flaky Pie Dough, prepared as for a blind-baked pie
• Brown Sugar Whipped Cream

Directions

1. In a 3-quart stainless steel saucier, add the sweet potatoes, scraped vanilla pod, cinnamon sticks, whole nutmeg, milk, cream, and sugar. If you’re using a scale, note the weight of the filled saucier now, so the reduction is easy to check later. Set over high heat and bring the mixture to a boil, then lower the heat to medium-low and keep it at a soft simmer; pushing the heat higher can make the milk curdle. Use a flexible spatula to scrape the pot often, especially along the sides, so milk solids don’t collect there. Cook until the sweet potatoes are so tender they collapse and the dairy has cooked down to a thick sauce, about 55 minutes. At that point, the saucier should be 19 ounces (535g) lighter than at the start. Alternatively, measure the finished mixture, cooked sweet potato included; it should come to 3 2/3 cups.
2. Move an oven rack to the lower-middle position and heat the oven to 350 degrees F (177 degrees C). Fish out the vanilla bean, cinnamon sticks, and nutmeg, then blend the sweet potato and dairy mixture in the saucier with an immersion blender until smooth. If the pot is too wide or splashy, move the mixture to a smaller container first. Whisk in the ground cinnamon, grated nutmeg, salt, and vanilla, then whisk in the eggs. For an extra-smooth filling, pass it through a fine-mesh strainer before adding it to the prepared pie crust.
3. Bake until the center is softly set and registers 195 degrees F or 91 degrees C, about 40 minutes. Let the pie cool for at least 20 minutes before cutting it with a chef's knife, wiping the knife clean between slices as needed. Serve with dollops of Brown Sugar Whipped Cream, if you’d like. Covered in plastic, the pie keeps for up to 3 days at cool room temperature.