Step 1: Preheat oven to 375°F (190°C). If using a homemade pie crust, par-bake it for 10-15 minutes, then let cool slightly.
Step 2: In a large bowl, mash the cooked and peeled sweet potatoes until very smooth. An electric mixer or food processor works best for a silky texture.
Step 3: Add the melted butter, granulated sugar, evaporated milk (or heavy cream), eggs, vanilla extract, cinnamon, nutmeg, cloves (if using), and salt to the mashed sweet potatoes.
Step 4: Beat with an electric mixer on medium speed until the mixture is completely smooth and well combined, scraping down the sides of the bowl as needed. Do not overmix.
Step 5: Pour the sweet potato filling into the unbaked or par-baked pie crust.
Step 6: Bake for 50-60 minutes, or until the edges are set and the center has only a slight wobble when gently shaken. A knife inserted near the center should come out clean.
Step 7: Carefully remove the pie from the oven and place it on a wire rack to cool completely. The pie will continue to set as it cools.
Step 8: Serve warm or chilled, plain or with your favorite toppings like whipped cream or vanilla ice cream.