Preheat the oven to 350°F (175°C) and line a baking sheet with parchment paper.

In a large mixing bowl, combine the purple sweet potato puree, granulated sugar, vegetable oil, and vanilla extract. Stir until smooth.

In a separate bowl, whisk together the all-purpose flour, baking powder, and salt.

Gradually add the dry mixture into the wet mixture, stirring until just combined. Avoid overmixing.

Cover the bowl and chill the dough in the refrigerator for about 30 minutes.

Once chilled, scoop tablespoons of dough and roll them into balls. Roll each ball in powdered sugar until fully coated.

Place the coated dough balls on the prepared baking sheet, spacing them about 2 inches apart.

Bake for 12-15 minutes, or until the edges are set and the tops crackle.

Allow the cookies to cool on the baking sheet for a few minutes before transferring them to a wire rack to cool completely.