Prepare your sweet potato by piercing the skin of a medium sweet potato and microwaving it on high for 5–7 minutes until tender. Alternatively, roast in a 400°F oven for about 45 minutes. After it cools, scoop out the flesh and mash until smooth, measuring out ½ cup for the dough.

In a large mixing bowl, combine ½ cup of softened unsalted butter, ¼ cup of brown sugar, and ¼ cup of granulated sugar. Beat on medium speed for about 2 minutes until fluffy. Gradually add in one large egg, 1 teaspoon of vanilla extract, and the mashed sweet potato, mixing until combined.

In a separate bowl, whisk together 1 cup of all-purpose flour, 1 teaspoon of cinnamon, ¼ teaspoon of nutmeg, ¼ teaspoon of ginger, ½ teaspoon of baking soda, and ¼ teaspoon of salt. Ensure to break up any brown sugar clumps.

Slowly add the dry mixture to the wet ingredients, mixing gently with a spatula until just combined. Avoid overmixing. The dough should be slightly sticky but hold together well. If desired, fold in any optional chopped pecans.

Preheat your oven to 350°F (175°C) and line a baking sheet with parchment paper. Scoop out the dough using a tablespoon and roll it into balls, spacing them a couple of inches apart on the baking sheet. If using pecans, press a half onto the top of each cookie dough ball.

Bake the cookies in the preheated oven for 10-12 minutes or until edges are lightly golden and centers appear set. Let them cool on the baking sheet for 5 minutes before transferring to a wire rack.

Allow cookies to cool completely on the wire rack to achieve the perfect chewy texture. Store in an airtight container at room temperature for up to one week or refrigerate for up to two weeks.